The One's raid team started out it's Cataclysm Raid Adventures with an adventure into Blackwing Descent, a new Blackrock Mountain based raid that picks up where Blackwing Lair left off. Literally in fact.
Our first venture inside brought us fairly swiftly face to face with Magmaw, a big firey version of the Crawlers from Hellfire Peninsula.
Breicor suggested that we all checked out the following guide for tactics purposes. and I decided it'd be handy to link it here, for easier reference.
NOTE - I didnt make this guide i'm just linking it from MMO-Champion for easy guild reference. I think it was an entry into a competition they ran.