Most of these games have longer play times. This is just since I installed Raptr, and those games I haven’t uninstalled after playing to free hard drive space.
Some games deserve amazingly long play times. Sometimes it doesn’t seem like it’s been as long as it has. Take Dragon Age for example; when I finished my first playthrough I had 80+ hours played. I felt like I had just started playing three days ago and I was enjoying the game so much I immediately started another playthrough.
Some people seem to think that the longer a game is, the better. This is especially true with RPGs. If it’s not at least 40 hours of gameplay then most people, “professional reviewers” included, will slam it. Meanwhile if I want to finish a game like Gothic 3 I’ve got to put in 50 or so hours. That doesn’t make the game better. Sure, having all that content on the side, in perhaps a sandbox style after you beat the game, would be fine with me, but honestly I was ready to be done with Gothic 3 at the 20 hour mark, and the longer I played the less I enjoyed the game. The less I enjoy the game at the end, the less likely I am to buy into the franchise in the future, which is the goal of the gaming industry at the moment.
That’s not to say that I want all games to be under 10 hours, not at all. It’s just like a book in my opinion. There is an unspoken limit to how short it should be at the minimum, and how long at the maximum, and if you go outside this range you better have a good reason. For instance, Portal. Only 3 or 4 hours long it was an amazing game, at a discount price. If it had come out at $60 it would have flopped.
On the other hand we have Dragon Age, with over 80 hours of gameplay on a single playthrough, it didn’t ever feel padded or like there were really hard moments just so you would die a bunch and pad the game time. Of course none of this applies to something like online play, whether it be some kind of PVP thing like the online portion of Modern Warfare or Online only like an MMO. It also doesn’t apply to second playthrough’s or other types of game options, only to the main story.
In short: If people are getting bored with your game before the end, it might be time to cut some content.
Manifest Pixel 
I like long games…a small part of it has to do with feeling like I “got my money’s worth” but more importantly I think it’s because I get immersed with long games. I spent well over 100 hours on my DA:O playthrough as well, and not all of it was actually playing the game. I spent a chunk of time just reading through all the entries in the codex, and I consider that time well spent too. That’s the hallmark of a great game to me, that I enjoy every second of my time spent playing no matter how long it is, or what I’m doing, and if even the less “active” parts of the game hook me.
I completely agree. A great game will keep you interested for every minute you play. But length is part of what makes a game great. If Portal had been 70 hours long it would not have been considered so good. By the end people would have had time to get bored with the gameplay.