Of the teams I was actively playing, not enough has changed for me to switch.
And of the teams I have, but am not playing much, not enough of a gain either.

Still doing:
a) Pal, 3x Shm, 1x Warlock.
b) Druid x5
c) Warlock x4, Disc.

Depending on how essential a dedicated healer is (for dispels), might trade something from the mixed team for a shaman on the main PvE team.

Not really into wow so much at the moment... I go in phases, between not playing much and logging 16-18 hrs a day for a month... so just doing transmutes and auction stuff for the last few weeks. Haven't quite finished the priests, but they've been an hour or two from 68th for a week. Still want to make DK's and get them to 68th for another 5 alchemists... And to level all alchemists to 73/75 or so, so they can immediately skill from 450 to 525 when Cataclysm arrives.

Lots of time still, and I'm making 30k a week even at my half-assed pace.