As some other persons have mentioned, the Bing imagery has been updated recently. It's especially a big update for me because several of the areas where I've mapped got a better view.
Most particularly, Guadix, a lovely and picturesque Spanish town has now a satellite view. It's a great feeling to see all the street that I've entered using GPS traces suddenly appearing (almost perfectly) aligned over the satellite view. Completing the town should be much easier now! I recommend any one visiting the area to stop by this city and visit the troglodyte district... and write down the name of the streets at the same time ;-) .
It seems that Lima also got new views, with a much better alignment than previously. I've also noticed that around Xi'an the high-resolution area has grown a lot, which should permit to map countryside roads.
Overall, a very useful update of Bing :-)