When Apple first created the iTunes Store, it was able to get all of the major record labels to cooperate because the company's digital media platform--which at the time included iTunes and the iPod--worked only on the Mac. The theory was that, if the store failed, there wasn't a huge risk since the wider world of Windows users--with over 95 percent of the market--was excluded.
The iTunes Store took off, of course, and later that same year, various executives at the company tried to convince Steve Jobs, unsuccessfully at first, that iTunes should be ported to Windows, opening up the iPod and its nascent iTunes Store to a much, much wider audience. Jobs relented months later, but only because doing so meant that Apple would sell more iPods. (Not coincidentally, years later he refused to port the iTunes software to Android since doing so wouldn't help Apple sell more hardware, which is the company's chief source of revenue.)
This mindset puts Windows users in a bad spot when it comes to Apple hardware, and it's a situation that has repeated itself over the years with other popular devices like the iPad and the iPhone: In order to use Apple's devices, Windows users--which, yes, constitute the vast majority of Apple's overall customer base--must put up with poorly-made software that is an afterthought for the company that produces it. (I'm looking at you, iTunes.) When the first iPhone shipped in 2007, I was one of the only people, possibly the only one, who pointed out, for example, that Outlook sync with the device simply didn't work; other reviewers clearly tested only with Macs, compliantly ignoring the PC as Apple does.
Of course, as the iOS software that controls Apple's devices matured over the years, the reliance on PC/Mac sync has diminished. And thanks to the "PC free" functionality in iOS 5 (see my review) and an evolving set of capabilities in Apple's iCloud services, many iPhone, iPad, and iPod touch users will be able to use those devices without a PC (or Mac) going forward. This is a two-edge sword, however. On the one hand, the PC sync stuff was always the weak link in the Apple device ecosystem. But on the other hand, by moving away from this sync reliance, Apple is pretty much ensuring that it will stop focusing on the PC at all, that its previous halfhearted efforts will seem substantial compared to what will happen going forward.
(Without getting too much into theory here, this is actually an opportunity for Apple to see beyond Steve Jobs' closed mindset and do the right thing by customers, regardless of which personal computer they've chosen. I don't expect that to actually happen, but you never know.)
So what's it like using the iPhone 4S with Windows?
It's gotten better since 2007, but from an iTunes perspective, not much has changed. The iTunes software has evolved slowly, and the device Info pane, from which you configure PC-to-device sync of contacts, calendars, and mail accounts, is almost as ill-featured as it was when Mobile Me debuted. But there are a few improvements. Contacts sync supports Google and Yahoo now, though mail and calendar is still Outlook-only for some reason.
Of course, you're better off simply configuring account information on the device, I think, and thanks to new Wi-Fi sync and iCloud features, the need to physically connect the device to the PC otherwise has diminished greatly.
Cynics will note that Microsoft offered Wi-Fi sync on the Zune several years ago, but whatever: The installed base of iOS devices is an order of magnitude bigger than that of the Zune and Windows Phone, which offers a similar feature. So this is a big upgrade.
Wi-Fi sync works pretty much as expected, though be sure to run through Setup on the device before enabling this feature. And you're going to want to do the initial sync via USB, assuming you have a lot of content to push over, but after that, you can pretty much stick to Wi-Fi sync. According to Apple, Wi-Fi sync will only occur when the device is plugged into power, but my iPhone 4S and iPad regularly sync regardless, which I'm OK with.
The only issue I've seen is that iTunes will occasionally throw up an error dialog about the connection not working; it recommends reconnecting. But simply clicking OK usually clears up the problem, whatever it is. I've seen this on both the iPhone 4S and iPad.
The services in iCloud are, perhaps, more profound, and they go a long way towards ending the need to ever connect the iPhone 4S to the PC. With iCloud, you can sync email (if the account is with Apple), contacts, calendar, and bookmarks, as with Mobile Me, but also reminders, notes, documents (Mac app format only), and other data. You can access your entire history of iTunes purchased music, TV shows, and apps (but not movies, at least not yet), meaning you can easily redownload this content at any time to any of your devices. I've done a lot of this, mostly with music, and it works very well.
You can also optionally configure the iPhone 4S (or other iOS 5 devices) to automatically download any newly purchased items (music, apps, books, and so on), ensuring that your devices will all have the newest content. And you can configure the iPhone 4S to automatically upload to (and download from) your iCloud-based Photo Stream, in which Apple collects the most recent camera photos. What this means to you is that you can take photos on the phone and have them automatically show up on the PC (assuming you've configured iTunes correctly), removing yet another need to physically connect the two.
To get Photo Stream syncing working on the PC, however, you have to do a little bit of extra work. This involves finding and downloading the iCloud control panel (which replaces the old Mobile Me control panel) and configuring it with an iCloud account (which can be your normal Apple ID). Then, you can optionally configure where your Photo Stream content will be downloaded (Pictures\Photo Stream by default) and where the upload folder is; photos placed in this location will be put in iCloud and synced to configured devices.
The nice thing about Photo Stream is that the resulting files are full-sized and full resolution; they're not downsized as is the case with Windows Phone's auto-upload functionality. However, there is a major problem too: Many of the photos I take with the iPhone 4S are upside down. I believe this is because I've used the Volume Up button on the device as the shutter button and this button is in fact on the "bottom" of the iPhone 4S, if that makes sense. Way to go, Apple.
I'm also not clear what happens to phone-edited files. For example, let's say you take several pictures with the iPhone 4S camera and then let it sit for a few days. These photos will all be copied to your Photo Stream, and fairly immediately from what I can tell. But then you pick up the device and use the new quick fix edit functionality to fix a few of the previously taken photos. Are these fixed photos now uploaded to the Photo Stream? In my experience, no. I still see the old versions.
Of course, you can still manually download photos from the iPhone 4S to the PC using Windows Live Photo Gallery or your photo acquisition application of choice. In this way, the iPhone 4S works with Windows as does any digital camera, which I vastly prefer to the way Windows Phone works; that system requires you use the Zune PC software, which doesn't have a way to rename pictures automatically when synced. (To be fair, Photo Stream uses the raw image names as well.)
The iPhone 4S integrates pretty well with a Windows PC. You have a limited set of options for account-type syncing, but that sort of thing is better served by on-device configuration, and your accounts should be managed in the cloud anyway, not through Outlook or some other Windows application. Content sync can occur over USB--which is great for large collections--or, now, over Wi-Fi, which works well. And thanks to new iCloud services, you can automatically push iPhone photos to the PC without ever bringing the device anywhere near the PC. Or, you can choose to acquire pictures as you do with any digital camera. Apple may neglect the PC in certain ways, but the iPhone has evolved to the point where you can do pretty much anything you want, and do so efficiently. So, yes, there are a few compromises, but the integration is there if you need it.