Not sure what's happened - my battery was very low, but after the phone has charged overnight, only the "google" screen comes on and then the phone goes off. Any ideas? Thank you!
I'd like to double Pontiac005's advice. That might be a bad USB connector. Search the forum here and on XDA and you'll find a bit about it. In a pinch, if you can stick in a different battery, you can see if it's the battery or the phone itself.