Well, I carry either a Cold Steel Vaquero Grande or a Voyager X2 (both with 6-inch blades and serrations). I like Cold Steel's serrations as they cut like a plain edge but have the advantage of a plain edge. They cut most anything and can even be used for yard work. I've got a half-serrated tanto 5-inch Gunsite knife, too, but it's brand new and I've never carried it.
With other knives, I'd choose a plain edge. If you've ever tried cutting something sinewy with a serrated knife, it's bump, bump, bump, bump. It can leave a mess. I agree with those who say that if you keep your knife sharp, you won't need the serrations. For social purposed, however, the fine serrations of the Cold Steel help.