simple

mabye too simple, but if you added an upgrades system etc would work out great.

Pretty good.

I'd add a system of upgrades like an auto firing and a speed upgrade for the firing, of course the points would then be a money system, but also maybe a shield thing because after the one hit it kind of kills the mood.

But it definatley was a good game but it wasn't interesting enough, and like the other guy said, music is vital.

Could use some changes.

Music is vital. There needs to be something to listen to while playing. It isn't that hard to grab something off the audio portal.
Lives. Miss one time and you lose. Maybe make a third of the buildings collapse each time a bomb hits?
Levels. The game should increase in difficulty at certain points.
Mouse aiming. Its extremely awkward and if you used this to make the game harder, all it does is create fake difficulty as opposed to real difficulty. If you think this will make the game too easy, consider adding in the above suggestion.
Different types of bombs. Bombs that explode into smaller bombs, slow but powerful bombs, small but weaker than usual bombs. Variation in enemies helps keep the user interested.
Bigger game area. If you add different bombs, such as fast ones or ones that explode into smaller ones, then it will be much harder to counter them in the current playing field.

Obviously I'm not saying to add these suggestions, but they are, however, something to work towards. I don't know the capabilites of flixel, but consider adding the above suggestions if possible. :)

Ehh... Its okay...

Not that great, but since this is your first flash, I am a little lineint. not my first time with this game type, but has better-than-usual art for this type of game.

Goof first go

Yeah, for a first go that was OK - obviously there's loads of directions you can go with it - upgrades, shop, multiple live, energy bar etc, You should add some of those things just to see how you can make them work
What I really wanted to say though is that the gun had disappeared off the bottom of the screen until I found the 'Show All' toggle - you should look into that!