Many people have tried, but I think Valve has come the closest to the vision of what a game like this is supposed to be. For those who are harping on value, I'm sure the price will come down eventually. After a few months, they'll probably have a 'weekend special'. Man though, I LOVE the animations in this game. It's so movielike, I was wondering for a while if they were using something like the euphoria engine to simulate nervous-system an skeletal dynamics. Then I thought, no, it's just a whole crapload of different prerendered animations that 'tween' into ragdoll at the right time. Love the drop to the knees animation. If you shoot them in the middle of that animation, they twitch again. This is what we're talking about with the standard Valve polish.
I also agree with those who say that tf2 probably has more staying power. It's a direct vs game, and those always have more staying power. But think of where they could take the ideas they've explored in this game in subsequent games! Firstly, I'd like to see them try their hand at randomized levels. I believe they're already doing branching paths through the maps. In the first map in the demo, the wall is sometimes broken when you drop through the hole, and sometimes it isn't. Secondly, I hope they add new kinds of boss infected. I'm already wishing for more than witch, boomer, smoker, tank. And man, they better use some of those death animations when I'm shooting combine in the next episode, or i'll be dissapointed
Errr... I gush