Microsoft Mobile (formerly Nokia) announced this morning that the free Windows Phone 8.1 OS update and the associated Cyan firmware update will soon head out to Lumia users. Microsoft completed Windows Phone 8.1 back in early April and had previously promised that it would ship to phones over the summer. So today's announcement appears to make good on that promise.

That said, a quick scan of Nokia's Software Update for Nokia Lumia with Windows Phone 8 page shows that, as of today, no wireless carriers are in fact rolling out the updates yet. Instead, they are mostly listed as "under testing," while some models, like the Lumia 810 on T-Mobile will not be getting the firmware update. (Everyone with Windows Phone 8 should be able to get 8.1 regardless of firmware availability.)

Windows Phone 8.1 is well-understood and represent as major update for Microsoft's mobile OS. Check out my Windows Phone 8.1 Review, and of course my in-progress e-book, Windows Phone 8.1 Field Guide, for more information.

Nokia Lumia Cyan is a bit less well-understood. In Nokia Lumia "Cyan" Firmware Update to Improve Imaging, I wrote about the one area of improvement that Microsoft Mobile/Nokia has gone public about so far. But in a new post this week, the firm provides a few more details.

Those imaging improvements will improve apps like Nokia Camera, Creative Studio and Storyteller, the firm says, and each will be updated separately. (My understanding is that these apps don't come "with" the firmware update but are rather still separate downloads.

Nokia Camera gets "a simplified user interface with one-tap access to edit and share pictures, and full-resolution zooming and re-framing," Microsoft Mobile notes, and you'll be able to access Creative Studio 6 directly from the app's Camera Roll too. This updated app is available now.

The updated Creative Studio 6 will be available soon and will include new filters and image enhancement tools.

The updated Storyteller app, which I think is available now, turns your best photos into short videos that can easily be shared with others.

Cyan will also include a new Nokia Device Hub that keeps track of when and where you last used Nokia accessories with your handset. The goal here, apparently, is to "help you track down a missing accessory," which is a little goofy. But it also provides handset-specific accessory recommendations. (I see Device Hub on my own phones, so it's not clear if this is an updated version or whatever.)

And if you're using a Lumia 520, 525, 620 or 720, your free Nokia HERE Drive will be upgraded to a free version of HERE Drive+, which provides downloadable offline maps for the whole world, not just your own region.

For those with a Lumia 1520 or Icon, the Cyan update will improve the audio quality in recorded videos with Nokia Rich Recording and Dolby Digital Plus 5.1 sound. The cameras will also be improved with better colors and low-light performance, continuous autofocus and improvements to RAW DNG images.

Of course, the big question isn't so much "what," but rather "when."

The official statement is clear enough, but vague. "The Lumia Cyan update will start rolling out around the world today and will be available for all Windows Phone 8 Lumia devices in the coming weeks." My advice is to keep an eye on the Software Update for Nokia Lumia with Windows Phone 8 page shows and not compulsive tap the "Check for Update" button on your phone. It could still be a few months depending on your device and carrier.