One important Microsoft product that wasn't discussed at all last week at Build is Surface. And I'm starting to think that maybe it's time to reassess this product line and realign it around the new strategy for Windows.

It's just two years after Microsoft announced its plans for Surface, and the market has already shifted. In mid-2012, the PC was getting smacked around by the iPad, and Windows looked a bit long in the tooth. By creating a tablet lineup that highlighted the strengths of Windows 8—such as they were—Microsoft was providing its PC-centric audience with a real alternative.

Or so it seemed. Surface hasn't sold very well, and as noted things have changed. The two big trends since then are:

An evolving tablet market. That iPad challenge has evolved into a predominantly Android tablet challenge and, more to the point, one in which the volume part of the market is in fact mini-tablets with screens in the 7-to-8-inch range. As Apple accounts for less and less of this market, aping their strategy with Surface makes less sense. And the version of Windows that specifically targets iPad, Windows RT, is dead in the water.

PC users stand their ground. Meanwhile, a considerable percentage of the Windows installed base—about 1.5 billion people, according to Microsoft—simply rebelled against Windows 8. They're not hugely interested in touch, nor are they happy about all that Modern UI getting in their way while they're trying to get work done. They want a Windows that is tailored to their needs, not to some imaginary market of hipster tablet users.

So far, Microsoft has addressed both of these needs in Windows.

With Windows 8.1, first, the firm made it possible and inexpensive for hardware makers to create Windows-based mini-tablets, and it took the first steps towards making this new Windows more usable by traditional PC users.

Those trends are amplified in Windows 8.1 Update 1, of course, with Windows now free on small screen devices and a host of new improvements aimed at traditional PC users.

But what about Surface?

Microsoft has to address the mini tablet market, and they will. I know that Microsoft planned to deliver a Qualcomm-based (i.e. Windows RT-based) Surface mini alongside the Surface 2 and Surface Pro 2 last year but pulled back at the last minute. I've not heard why, nor have I heard about any more recent plans, but I suspect it has to do with Windows RT. And when Microsoft does announce a Surface mini sometime soon, I further bet it will be based on an Atom chipset like all of the other Windows mini-tablets. It's clearly where the market is heading.

But what about that traditional PC crowd? Doesn't a touch-based Ultrabook also make plenty of sense? Something with a much more reasonable screen size (13-inches, minimum) than the tiny screens on the Surface 2 and Pro 2?

I think it does.

And I think such a device would be embraced by Microsoft's core audience of IT pros and knowledge workers. The businesses that are tired of crapware and of PC maker-modified versions of Windows. It could become the de facto standard for the small businesses that don't have the cash or technical expertise to customize their own Windows installs. And it needs to happen this year.

Basically, it's time for Surface to adapt to the changing market just like Windows is. In fact, these things should go hand-in-hand.