The DLC has been released and there are two separate downloads. One is just the Bonfire of the Vanities (priced at $4.99). The other is the Bonfire of the Vanities + the Templar tombs unlocked.
I've heard that this DLC is actually worth it. You get 13 additional missions, and 9 additional assassination missions, so it does add a lot more to the game, as was expected. So compared to the first DLC, it appears to be a vast improvement. I think I'll pick it up (and the first DLC) once I finish up Mass Effect 2.
Lastly, the three tombs were the Collector's Edition bonuses. The Master Edition came with two of those tombs; if you got the CE from Gamestop, the third tomb is also included. I got the CE but not from Gamestop so I haven't played one of those tombs, but it's definitely not worth the price of admission there for 10-15 minutes of additional gameplay.