I am in general a pretty forgiving guy. I'll put up with a lot of crap in my games (I played Fracture to completion). But the ending to Hydrophobia is simply unforgivable. Yes, I know it is supposed to be episode one in a series. But that is no excuse for what they did. 
 
The game ends in the middle of a cut scene. In the middle of a mission. Without even the slightest attempt at wrap up.  A complete 180 from episodic content, ala Telltale. 
 
I actually reloaded the final checkpoint and played the last bit a second time, for sure that I had accidently skipped part of the cutscene. No, it really is a complete abrupt ending.  It is like they developed the entire game as a whole, then just cut it up into episodes without any regard to where the cuts were.  
 
The worst thing is that I liked the game. I would have even been willing to give the second episode a shot. But not after that ending. Simply terrible.

I never bought that game cause I heard that it had a cliffhanger ending (although I didn't know it was that abrupt).
I wonder if there will even be an episode 2.

i heard the game could have been great had they put more thought in to how the game played out, as it is even with the "Pure" update the game feels like the training wheels of a much bigger, better game. The challenge rooms are the best thing in the whole package and somebody over at the studio should have said "hey lets do more of this and just shelf the rest of this crap, oh and tell those voice actors they are fired"

Downloading the demo now.

My GOD, i can sympathize with you, what a load of crap that was, the really cruel thing was that i was really enjoying the game, i mean the physics was amazing, and then it ends just when its getting interesting, all i can say is that i wan't my Microsoft points back, if i had known that i was going to be so short, i never would have bought the bloody thing!!!

Thanks for the heads up, will probably avoid (even if it goes on deal of the week).