I shook off my fears about Heroic SL and tanked it twice this weekend. Was actually a lot easier then I thought it would be. The first run was with 4 people from a different guild, and they all but invited me to leave my guild and join theirs cause they were so impressed. The second was a little rockier despite being with 4 people I run instances with quite often, but I managed to be third on the damage meter (missed number 2 by .03%). That's 4 more people converted to the "ZOMG Paly tanks rock!" club and 8 more converted to the "ZOMG tanks do damage?!" club.
Also went into Heroic Mana Tombs for the first time, and I must say, that place is a living hell ... Warlock, Feral Druid, Elemental Shaman, and Holy Priest in group with me. I gotta say, it was not fun >.< But we managed to get it done.