My battery has been acting strangely. It would drain VERY rapidly with iOS 7.
Now with beta 3 it's just sucked the life out of it.
Right now, the iPhone's connected to my iMac and there is absolutely nothing going on; no Apple logo, no battery charging, no sign that it's on at all - just a black screen. Bricked.
iOS7 bricked my iPhone.
Dead.
If you can't restore the phone via DFU or just holding down the home button whilst connecting to computer, either your cable/port is fecked or your battery/charging circuit has gone pop.