http://fronttowardsgamer.com/2011/06/11/e3-2011-deep-silver-swings-for-the-big-leagues-with-dead-island/
Fourth, role playing elements.They're all the rage, and any game worth its salt has them now-a-days; Dead Island follows suit nicely. Despite forcing the players to choose between four preset character models, the game allows you to build your character to your own style of play. The game has an "adrenaline" mode that you gain after a set number of zombie kills or over time that turns you into a death-wielding zombie killer, allowing you to massacre zombies around you, and it's one of the talent trees you can focus on upgrading. There's also a weapon/melee talent tree you'll want to upgrade, as well as a support tree, and there aren't enough points to upgrade everything. There also hasn't been a level cap announced, but during the demo, we were playing level 21 characters with some pretty hefty weapons choices.