Yesterday, we reported the Google Maps 3D Street Views are now back in action. But then I only reported that right clicking on the map was the only way to turn them on. I was wrong.
Alvin from the Google Maps team said that when you are viewing a street view image on Google Maps, you can press either the T or 3 key and "something fun will happen." That something fun is the 3D view will turn on. I tried it, and it doesn't seem to work on Chrome on a Mac, but it does work on Internet Explorer on a PC. Here is a picture:
Forum discussion continued at Google Maps Help.