But is that a good thing? I hate to keep harping on it, but Fullbright brings up Portal for me (a game that seems destined to redefine what we think of as games this year)-- there's a game that only takes a few hours but delivers an experience that lasts much longer than that. In terms of MMOs the current trend seems to be both towards shorter gameplay and less investment for that gameplay.
MMOs may be the exception here-- you sit down to create one character, and heading into a persistent world should make you want to be there. But with many MMOs on the market than before (and an older, busier audience than ever), the trend seems to be headed towards shorter games, not longer. That's not to say that a great game shouldn't cover the subject (no game should end before its time), but designers are feeling more and more pressure to make things short enough to keep it interesting, rather than throwing in random FedEx quests to brag about a few more hours of gameplay.