Pure fun, even with it's high degree of consolitis.
For me, the biggest problem with the game is that it's really not designed for the PC. The UI is pretty bad, the graphics simply suck and worst of all is the microstuttering you get when using a keyboard or mouse (jerky movement especially when moving the camera with the mouse).
However, the game has a good community and several mods have been released that cures the game (somewhat) of "consolitis". Search for "Dead Island config tool" in Google, and ye shall find the mod which every single PC user should have. It fixes the microstuttering, allows you to improve the shadows and lets you increase the awful default FoV which is at 62,5 degrees (lol).
With this mod, the game becomes a lot more fun. Yes, the graphics are pretty horrible and the voice acting should have been better, but it's still a very fun game. The melee combat is visceral, and dismembering zombies looks and feels cool. I've started playing through as the gun specialist chick this time around, and though ammo is scarce and guns don't really become available until Act II; it still opens up a new playstyle.
Climbing up to an elevated position where the zombies can't get to you and start sniping is good fun - until you run out of ammo that is.
All in all I really like this game. There's a good amount of variation in both weapons and environments to keep you glued to the screen for hours, and the atmosphere (especially in the city) sucks you in.
I'm giving this game an 8 simply because of the high fun factor. After all, this is why we play games, no?