Well i run a node (not exit) and yes it's better then nothing, but to fully trust Tor is a big nono, i said nothing else. Protections from private company or country's yes..but protection from GCHQ/NSA probably not.
And no you can trace it thru the ISP's, the problem is the latency, Connection from here to there in that millisecond trace one...and so on.
>>nix23+(OP)
If you are speaking about the timing attack, then you should consider I2P. It makes them significantly harder. In general, I agree that if your enemy is NSA, you can do very little. But you can make their life harder, and you should.