Several people are very vocal about bombers, thinking that they are OP due to bomber-first builds being effective on some maps. I'm here to present my point of view, and the reasoning behind it:
Bombers Are Fine.
The reason they are fine is that air-first is incredibly risky. On a small land map, you are sacrificing early land scouts and raiding units. This means that not only are your expansion engineers left helpless to your enemy's raiders, but you are unable to raid his expansion engies either. If that bomber fails, you have set yourself back by a huge amount.
But that bomber will kill all my engineers!
Yes, if all of your engineers are bunched up so they can be hit in one pass. But in practice that will never happen.
It is also possible to dodge, indefinitely, a bomber's bombs if you see them coming. Once you see the angle of approach of the bomber, you can infer it's likely target. Select any engineers along that line, and move them in a diagonal direction to the bomber's approach. Crude ASCII art displaying this:
--|-------
--|-------
--B-------
------E---
----/-----
--/-------
B is the bomber, E is your engineer.
But bombers will still kill all of my units and power before I can kill them!
The math doesn't add up to support this claim.
If you send an early t1 scout out (which everyone should be doing, by the way), you can usually see the bomber coming and have AA up in time to kill it before it even gets it's first hit in.
If you forgo scouting, you can still react to it in time. Remember that a single stationary T1 aa will stop anything less than ~4-5 bombers and create a nice no fly zone over your base, and costs 150 mass - or the price of three tanks. They build quick enough that your ACU can have one built as the bomber comes in for it's second pass. Even if it kills an engineer on both passes, you're still in the lead mass-wise - plus you have the advantage of having raiding units, and your enemy has no land units yet.
But bombers can double drop!
Double dropping is only effective vs stationary targets. Vs units it's useless if they're moving out of the way, and T1 engies will die to a single bomb so it's redundant.
The only way it could possible be useful would be to bomb someone's early pgens. I've yet to see this work as any high level player will have AA up before the bomber has enough time to kill any pgens. Remember that double dropping necessarily slows down the bomber, allowing any AA to shred it to pieces. It could only *maybe* be of benefit on the first pass, and since you cannot kill pgens in one pass it's a non-issue.
If, however, you're talking about bombing things that are in a line, then that's simply good micro in practice. Use your own micro to swiftly move your engies out of harm's way, and rush AA to kill the bomber. Then press your land advantage as hard as you can.
On <insert medium to large map> bomber rushing is risk free! I can't get my land units to his in time to press any advantage!
Not directly, no. But the goal isn't to kill his entire base - just to delay his expansion while expanding as much as possible yourself. Varga and Palms are good examples of this.
Due to the increased travel time on those maps, you also have a larger amount of time to scout his bomber first and get defenses up ahead of time.
This is no fun, I keep getting killed by bomber first and it's breaking the game.
If it truly were an "I-Win" button, why is it not used by everyone to instantly guarantee a win? Additionally, why did "bomber week" have so few replays submitted to it? If it really were as prevelant as some people make it out to be, the thread would've been overflowing with replays showing noobs beating pros thanks to the "Epic Awesome OP Bomber First of Unlimited Pwnage".
The answer is that it is an incredibly risky tactic that requires a large amount of skill to pull off successfully. If you try this vs a high level opponent, they can and will counter it, and you may be putting yourself at a disadvantage.
I've yet to see any "non-pro" players successfully use a bomber first build. Why? Because it's very easy to crash your eco and screw up the micro'ing of the bomber, giving his enemy a net advantage.
That leaves only one matchup available, and typically the group I see complaining about bomber-first... "pro" vs "noob". In which case, the latter party complains that the game is over too quickly. Well, I'm sorry, but if ZLO_RD or any other top player is playing RandomNoob#10051, the former is going to win no matter what tactic they use. Length of the game is irrelevant - and if there is some magical minimum amount of time that a game should last before it's "over" then I'm not aware of it, and if there is we should consider adding No Rush modifiers to ranked.

The other typical complaint in the above matchup is that it's "no fun". Playing pros when you are a noob is never "fun". When I was a noob I was repeatedly and effortlessly dispatched with the back of any of the then-current pro's hands. That's how you learn. You play the best to learn how they are the best, while iteratively improving your game by reducing the number of mistakes you make. Unfortunately there is no way to speed up this process or minimize it's unpleasantness. If you don't like it, then I would recommend avoiding playing those pros for now.
Well, I still think bomber first is lame. At least I have my Code Of Honor.
http://www.sirlin.net/ptw-book/more-on-losing.html
In all seriousness, 1v1 is a competitive game. People will always try to use whatever is available to them in game to give themselves an advantage. As Pilot says, "if it's part of the game, use it. If it's OP, use it more!".