After upgrading to 10.10, I can't login anymore. The problem seems be related to graphic card (computer is Lenovo S10e) and new unity interface. I wonder if anyone have similiar problems and if some solution exists.
Based on your tags, it seems you are using Unity, the Ubuntu Netbook Edition's new interface in 10.10. Can you confirm that?
If that's the case, then you are probably affected by this bug:
In that case, I have the same problem, as my installation in a Virtualbox virtual machine gives the same behaviour when I enable Unity.
Hmm, that doesn't sound good. You're probably affected by the bug the person above noted.
You might want to try reinstalling--if that doesn't help try burning and installing the Desktop version and running sudo apt-get install ubuntu-desktop edit: sorry, the actual package name is ubuntu-desktop
installing "fglrx" resolves the issue.