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.
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.
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.