Pocketnow have published some pictures claimed to be from taken from a Windows Mobile 7 emulator image. The image dates to around 2006, and likely bears little resemblance to what we can expect to see in two days time.
While the UI is clearly dated, Windows Mobile 6.5 still has to catch up to the use of transparency and gradients as demonstrated in the images above.
Interestingly these screen shots do lend credence to this picture of the HTC Universal which Eldar Murtazin claimed was running Windows Mobile 7 and which were dismissed out of hand at the time. It is now clear that this was in fact the case, again demonstrating how long Microsoft has been working on the OS.
See more screenshots at Pocketnow here.