Even if I get some hate from this, I applaud Sony. They are just trying to protect their console, you want CFW? More power to you, but there's no reason why you should argue on the reasoning behind why Sony wants to ban those users. Besides piracy, I'm pretty sure that this comes in direct result of Black Ops II, and the small handful of users that have modded/cheated online.
Stealthing isn't a guarantee, people who tried it when the first ban wave was rumored still got detected and were sent a warning. Simply changing your param.sfo won't help, deleting pushlists could help BUT if you've already gone online, you've sent Sony all your info anyways. There's many many ways they can be spying on us, we won't know until the bans occur and we get some solid data on what they are doing.
Like pandulce said, look at Microsoft. They have never warned you, they simply ban you during one of their waves and it's game over.
I'm surprised Sony has decided to be nice about it and warn everyone for the second time. I'm sure this is far beyond a scare tactic, because they have proven they can see what we do when they managed to send us the 1st warning email. (I'm sure many of you still remember that).
This is easily solvable, stay offline with your CFW and get a new OFW PS3.