Just beat the game... probably clocked in at about 10 hours.
Absolutely loved the campaign. It wasn't too long, but it was damn enjoyable. The writing was top-notch, and the story blended very well with the first 2 movies. Lots of fan service, and being a huge Ghostbusters fan (I bought the Ghostbusters outfit on Home >.<), I ate all that shit up.
Graphically, it's stunning. It's unfortunate that the game has some low-res(ish) textures that mar the beauty of particular scenes (towards the end of the game). There are some scenes that are really impressive, tech-wise as well (debris/book pages/etc. flying everywhere - wow; hall of mirrors fight - wow x2). The lip synching could've used some work, though - but the faces of the characters are rendered very well. Also, for some reason the devs chose to use videos rather than the in-game engine for a lot of the cutscenes (RE4 PS2 style). It's so stupid, considering that the cutscenes that are rendered in-game look fantastic and even better than the cutscene movies half the time (no video artifacts, etc.). Ugh.
Gameplay-wise, it was easier than I hoped. There are some parts where you don't know what you have to do initially and will result in getting wiped a few times, but aside from those handful of moments, I didn't really have much difficulty in this game.
The boss battles are fun and sights to behold, but again, once you realize what you have to do, they're fairly easy.
Anyway, I've yet to play Multiplayer because it seems the servers are still down - I've yet to find a game.
Even without multiplayer I feel like I've got my money's worth. I'm going for a second playthrough right now to find the rest of the artifacts and scan some more ghosts.

I can't imagine how much fun multiplayer will be with 3 friends bustin ghosts with me.
Bustin' makes me feel good!
Captain N said:
Can you pick Professional from the start or is it something you earn after beating the game?
You can pick it from the start.