Be sure to download anything you want to keep…
On April 29, 2011 videos that have been uploaded to Google Video will no longer be available for playback. We’ve added a Download button to the Video Status 
page, so you can download videos that you want to save. If you don’t want to download your videos, you don’t need to do anything. (The Download feature will be disabled after May 13, 2011.)
I don’t understand why Google doesnt just transfer the videos to YouTube.
I was thinking the same thing, but my guess is it would be too cumbersome as to where to put them. I think there would be too much whining no matter what they did. The most logical thing I could think of would be if they created a “Google Video” account to put all the videos in…but I could still see people bitching about that too. I think it’s just easier to warn people and then take the whole thing down. Save some server space.