I am implementing google maps for android. I created a test application and inserted all the permissions etc in that application and the application worked flawlessly.
2 possible reasons:
1. this part:
should right before the closing application tag.
2. Most likely you have some sort of problem with your key. Try to generate a new by deleting the debug.keystore folder and running a project. then register it again via the console.
you can use this guide I wrote to do just that:
Google Map API V2 key
Update:
Check this for a second:
it looks that the package you set here is not the package of your application and should be: