Grim Views

This guy has a bunch of videos out for each of the healer classes. I don't know how accurate they are, but they seemed pretty detailed.

Overview

Disc Priest
Holy Priest
Resto Druid
Resto Shaman
Mistweaver Monk
Holy Paladin

The latest news seems to be that resto shaman and resto druid are the best.

In general Shaman and Druid seem to be getting rave reviews for all specs.

IMO resto druid should always be the best. I honestly find their theme the best, even over priests.