James Patterson's Zoo. Basically, imagine zombie apocalypse but with crazed mammals.
It's a high octane thriller but lacking greatly in substance. The characters are flat, the science shatters my suspension of disbelief and the writing is amateurish with chapters telling of an animal attack placed in between chapters telling the protagonist's tale. Not to mention the use of some just plain bizarre metaphors and similes. The ending sucked too. Actually, ending's the wrong word. It's almost like a "to be continued..." message.
Finally, the most grating thing are the radical environmental and Luddite messages in it delivered with the subtlety of a dam failure.
Bottom line: idea is good but Patterson screwed it with terrible writing and stilted pacing. Personally, I think Cornova's PokÈ Wars is better written and executed (even if Cornova writes fanfiction and Patterson's a professional author).