I was checking out a few lakes on bing maps today and just for fun I clicked it over to the "birds eye" arial view. If you like a metro lake and the water clarity is decent, you have to check this out. Springtime weedlines and structure points are clearly visible. Shallow depth changes are pretty easy to see too. Some of the lakes still have ice but some are clear, depends on what time of spring they did the mapping. It also depends on where you scroll on the lake some parts are taken during thicker ice and some parts are clear so if you find thick ice move around a little and it might get better. It doesn't work to far out of the suburbs but it's fun to look at either way.
Ive been liking it as well. However, like you said, the Ariel and the Birds Eye views were taken at different times. Most of the lakes Ive looked at had spring Ariel views, but early winter Birds Eye; so most of the weeds are gone.