I had the same problem as you did... after bricking it, when I plugged in the charger it would buzz, turn on, turn off, buzz again, etc. I went to a Nokia Care Point and they tried to flash it for me there. They said they couldn't do it either. Now they have send it to the "Laboratory". I should have it back in 2 weeks (!) - either fixed or replaced.

The guy from the NCP said that I should probably go to them to update the firmware in the future, just in case. WTF is that about, right? It is a 600 euro phone, it should simply work.

Anyway, that is what happened to me. I suggest you try to find the nearest NCP and pay them a visit. Sorry to hear you are in the same situation as I am.

@others, is it better to flash the firmware per wiki instructions than using NSU?