We're not a big fan of this story but let's get it out of the way since it's sure to make the rounds.
phoneArena, a fairly reputable site, has received a photo of what they claim is a Nokia Lumia 900 running Apollo" aka Windows Phone 8. The shot really doesn't reveal much and there are lot of inconsistencies such as missing soft keys and labeling on the Nokia hardware and the oddly numbered "Apollo" version number.
The shot can easily be faked by loading up a pre-fabricated image on the phone and Photoshoping those three image-dots out. What is supposedly shown of the OS matches the Windows 8 login screen but that seems a bit of a stretch.
Bottom line: there's no evidence this is real as phoneArena conveys nothing about the tipster e.g. their credibility, do they know and trust them, etc. Seeing as not very much is revealed in this photo and it can easily be faked, we're going to say this has very little value at this point.
We would certainly not count this as evidence for anything and while we know you're hungry for info on Windows Phone 8, we suggest eveyrone just hold tight for a little while longer.