Well due to the hours I keep, while I have an awesome guild, I don't get to play with them often, so I'm left using the RDF. I also fell in love with thanking in Cata and pretty much for the reasons you mentioned. Enjoyed it right up to my first few heroics and had almost the exact same experiences you mentioned.

DPS abusing you for trying to be professional about things and generally being unmitigated tards.

Personally though I still love tanking and I still do it. I even tank at least one normal every day even though I don't need to, because I figure it's helping some folks to get an instance in that they normally wouldn't.

It also means though that I'm very, very quick to drop a group if they look like tards. I'll put up with folks that are new. I don't mind explaining fights or marking or CC. I do NOT put up with jerks or 'gogogo'. First time somebody starts being a jerk, I vote to kick, if it doesn't go through, I leave. A 15 minute break won't kill me and it's insta-pop after that.

You have to have a very thick skin to keep tanking pugs in cata. Nothing against you if you don't want to develop one. It shouldn't be a requirement.