Well done. Keep working on this one. It needs a some more levels and harder challenges. Also, try to think up another time-travel mechanic. (I'm assuming that you've played Braid.) If you can create one (or two or three) more time-travel mechanics, it will keep the player interested for longer.
It needs some type of goal, or at the very least needs a score counter. Trying to stay alive against random blobs is not very engaging. Also, don't make the player switch back and forth between mouse and keyboard, especially when the first few seconds of the game are so critical.
Really good concept. You could develop this into a solid game. Currently, I see two problems. 1) Building placement is too random, and you sometimes generate way too many building on top of each other. To fix this, you might have each new instance of the building check to see if it collides with another building; if it does, delete the new instance. 2) The jump ability is critical to staying alive, but it's hard to tell your altitude. To fix it: add a blob shadow projector under the player.
I think you've done well with the visuals and the feeling of tension. It's very dark and hard to see, but in a good way. The gameplay is frustrating, though. Every game is different, right? It's randomly selected which actions will trigger the bomb and which will detonate it? That's the way it feels to me. If so, then that's a big problem because the player can't learn anything, and he can't get better at the game. It's just pure luck if he wins or fails; if there's no test of skill, then it's not a game. You could really improve this game if you added some type of logical system behind defusing the bomb. Then, the player would eventually learn your system, and they'd feel good about getting better at the game.
 "jerry clouds"){kind=icon}
 "Absolute Time"){kind=icon}
 "Retro Runners"){kind=icon}
 "A Maurading Guy (Ludum Dare version)"){kind=icon}
 "City Runner"){kind=icon}
 "Cylinder Run"){kind=icon}
 "BombUniverse"){kind=icon}
Ya, I'm working on a cleaner non-ludum dare version that is more interesting. I will also attempt to have better circular collision detection.