I had planned a day of relaxing with Portal 2 but on starting Steam (for the first time in a couple of weeks) I was greeted with the following message in the terminal:

Error: API mismatch: the NVIDIA kernel module has version 270.41.19,
but this NVIDIA driver component has version 270.41.06.  Please make
sure that the kernel module and all NVIDIA driver components
have the same version.

I'll confess I don't really know what it's talking about when it says driver. The verion of nvidia-current is 270.41.19. I thought that was the driver and module, all in one.

I use the X-SWAT PPA and I have noted that the nvidia-settings package has boosted to 275.09.07. As this is just a settings application, I don't think this mismatch has anything to do with this. It's also not the same version as the problem being described.

I'd rather not purge back to the standard Nvidia driver as it's less than stable on my GTX580. I would accept an answer that takes the manual setup and makes it recompile when the kernel recompiles (ie, some DKMS wizardry) but it has to work. I don't want to drop back to text-mode every time I restart after a kernel upgrade.

Edit: Minecraft works without a single complaint about driver versions. Penumbra dies with roughly the same error when entering a game.