I recently completed the single player portion of Might & Magic: Clash of Heroes for PlayStation 3. It took just a shade under 45 hours, over the course of several weeks, to complete the story and earn all of the single player trophies. I haven't even played online yet. This game sells for $14.99 and I would have gladly paid more. It has incredible value for the length as well as quality of content.
About 4 months ago I borrowed Modern Warfare 2 from my brother, so I decided I would finally play it and give it back to him. As of this writing, I am 4 hours into it and I know I'm at least three quarters of the way through. When finished I will have most of the trophies. I am enjoying it very much, but this game is just way too short for the cost. It sold for $59.99 when it released. I did not buy it, but I kind of feel bad for those that did if they expected a reasonably long single player campaign for their money.
I guess sales sale figures don't lie (much). Take a look at this and this. People obviously want to play Modern Warfare (online probably) more than Clash of Heroes. I'm more of a single player type of person (I play online a bit) and I just can't bring myself to pay full price for a fraction of a game. I get that these are two different types of games. I understand that Modern Warfare 2 was expensive to make, and I don't blame developers and publishers for trying to cut costs. I just wish it didn't have to be at the expense of reasonable single player game length.
This was also posted at http://www.supergamerbros.com.