GMail down?

It seems as though GMail is not working (at least where I am in the UK):

Server Error

We're sorry, but Google Mail is temporarily unavailable. We're currently working to fix the problem -- please try logging in to your account in a few minutes.

I wonder why. Does anyone have any details? There doesn't seem to be any news anywhere about it. POP access also doesn't seem to be working.

Update: Now it's not responding. How can I check my email???