Now the big G is working to automatically migrate all our videos to our youtube account and hosted Google Videos will remain accessible on the web till then.I dont know how much time will it take for Google to do this but if you want to move your existing content from Google videos to youtube now you can do that by following the procedure below :
1 ) Simply login to your Google account.
2 ) Visit your Google video status page
3 ) Now at the bottom of the page below your uploaded videos you will see an extra button Upload Videos to Youtube next to the delete button as shown below
4 ) Select the videos you wish to migrate now to Youtube and click that button.
5 ) It will take you to Youtube account where you just have to click publish as shown below and your video would be uploaded to Youtube.