So today is apparently a day for Indie Game Developers to write articles about game length and how it often plays into how a game's received. "It's too short" is a common complaint indie games often receive. And while I'm not a true indie-developer just yet, I think I have something to say that I haven't seen in the other responses.
From what I've seen from other posts (linked below), the general consensus is that size doesn't matter, and in fact, longer games are often WORSE because they are often full of padding. People have cited JRPGs that run up to forty five hours as opposed to wonderful indie titles that only run two hours. "I appreciated the latter so much more!" is the general consensus, and so you should!
If the 45 hour game honestly sucked.
Here's how I break this argument down: Size doesn't matter. What matters is how you feel once you're finished with the game.
Now when I say "finished" I don't necessarily mean you've beaten the story and unlocked every super l33t X-Box live achievement and can tell me exactly how many mobs spawn in the Dungeons of Solitude Basement Level 3. I mean, when you personally have finished your experience with the game.
It's much easier to finish a 2 hour title than it is to finish a 45 hour one. If you finished the 2 hour title and feel unfulfilled, you will most likely go to the first thought that crosses your mind "It was too short." I mean, if your experience wasn't what you expected and the end credits are rolling, more often than not, you'll feel like it could've been what you wanted if it were only a bit longer. You were hooked by the exposition, enjoyed the characters, but felt it just wasn't enough. It ended too soon.
As for the 45 hour game, more often than not, if you're not digging it, you'll quit by the 10 hour mark and claim "it wasn't interesting enough to keep me engaged, it must've been full of padding". But, to be fair, you've played more hours on the 45 hour game than you have on the 2 hour game. How do you know if the 2 hour game wouldn't have left you with the same impression if it had been 10 hours long?
What I'm trying to get at is this: as long as the game feels finished and fulfilling, the length is accurate. If it feels too short, the story hasn't been fully explored and there's a pacing problem. If it feels too long, there needed to be cuts - the story dragged and, once again, there's a pacing problem.
On the whole, I prefer more over less. Not because I like my video games with repetitive, dull tasks or boring sub-plots, but because I love more good story. A short good story with awesome, fun game play is GREAT! A long good story with awesome, fun game play is better just cause there's more. I am an ardent believer in "two scoops are better than one" (as long as said scoops of imaginary ice cream don't have any calories. XD).
I'm not a true indie developer just yet. Read the peeps below for a real developer's insight. These are just my two cents on the subject.