I also got the email yep, but never even dared to go back online. Hell, I'd go back to OFW if need be. But didn't know if that was going to guarantee me 'safety' even if you supposedly clean up anything having to do with the JB.
Personally I never used online after I jb'd in late September. I always had the Internet Option on the PS3 set to "Off" and would unplug the Ethernet cable from it. Never ever did I go online besides the very first day Charles became available late that night before it got all popular the next few days. All I did was redeem my Cerberus DLC code for ME2 and log out.
Haven't even played a game since the 'bans' started occurring. You hear reports of people playing completely fine without problem for days, while others mention that as soon as you go online for 10 minutes you'll end up getting banned.
Kinda in the same boat as you. Honestly I'm still a bit stumped on what is going on, nothing solid yet.