Overwhelmingly meh.
Okay, so wet is kinda fun. For the first few levels of cutting down bad guys and sliding on your knees, and then you start to realise that it's effectively the same thing over and over. There aren't enough moves, and there's only so many times you can run up a wall or slide on your knees. Sure, swinging from poll to poll while shooting is fun, and so is upgrading your powers and stuff, but It's just nothing new or even very exciting after a while. The gameplay can be cool looking, but the formula of combat stays very samey. It's either kill everyone and move onto the next area, or it's block the doors to stop them coming out.
One thing I did really like about Wet though (other than the music) was the massively underused traffic hopping sequences, which although are little more than a quick time event with on the rails shooting, they are very exciting and kinda something to mix up the gameplay. There's just not enough of them.
My main issue with Wet is that it is super derivative not just of other action games, but mainly of Kill Bill, which it tries to emulate everything about, from the characters to the direction to the music.
Overall the game features a boring story, crappy characters (Ruby is annoying as hell, and totally unlikeable because of her mary-sueness, where she never misses, never looks stupid, never stops swearing and being aggressive. There's also next to know replayability value in the game, because it kinds gets dull the first time around anyway.
Get stranglehold instead, which has more style, cooler destructible environments, online play, and is more fun. Failing that, get Enter the Matrix, which Wet rips off anyway, but is less than in nearly every area.