I'm going to post a review in the near future but just wanted to give my impressions.
It's basically Citadels if only the drafting mattered, as you do very little on your turn. Also much more tactical, with much more catching-up and less long-term strategy (ANYONE can win at ANY moment).
That being said I think the game is very great and much better than Citadels for 5-8 players, because you don't have to sit through the individual turns (they take only a few seconds), but it's nowhere near as satisfying with 2-4 players, primarily because the mechanics of a race don't fit as well with only a few runners.
The feel is still very similar to Citadels - lots of douchebaggery, so don't play with people who don't like that, and you should probably use an egg timer during the draft...
I don't think it replaces Citadels because Citadels is still great with 2-5, but with 6-8 I'll definitely play Lost Temple, and with 4-5 I'd have to think about that particular situation about which one to play (or Mission: Red Planet... so many good games by Mr. Faidutti!).
Anyway, those are just my initial impressions - this game is currently criminally underrated. I think a lot of the disappointed comments are coming from people who didn't know what to expect. It's light, it's chaotic, the strategy is almost all bluff and psychology, and it's really fun.