For me it depends on the replaybility of the game. A game like Max Payne, while great fun, there's nothing to gain from replaying it (unless you really really liked it), so I wouldn't pay $50 for it.

That being said, there are plenty of games that clock in around 10 hours or so that offer unlockables that up the replayability(similar to gaining medals in the Rogue Squadron or Medal of Honor games). That may sway me into spending more.

Games like KOTOR strike the perfect balance, IMO, offering gameplay that can take some 15 hours, other 50 or more. Then there's also the incentive of playing through as a different type of Jedi leading to some big differences in gameplay. I shelled out $50 for it and wil likely buy it again after it's price drops (played through it twice, over 60 hours total).

That pretty much sums up my gaming philosophy right now. I simply don't have the time to expiriment with games any more. So, if a game is rated 9/10, 4 stars, etc, I may buy it regardless of length. (but never, ever pay retail!)

That said, I do appreciate if I know about how long the game is before I start to play it.

The only single player games I like are RPGs, which can guarantee at least 40 hours of gameplay, and even then I probably won't play it twice unless it has a randommizer like daggerfall did. Splinter cell was given to me as a gift, and I had to force myself to play it over several months, cause I didn't want to waste the game over 1 long weekend.

I am all about replay value. Thats why a company like blizzard, with a great free online service battle.net, will always be favored in my book.