Not bad. The quality of the writing was good, but it was sometimes a bit dry. The story was interesting, if slightly more slowly paced than I would've liked for this kind of book. It kind of took a lot of the "thrill" out of what I otherwise would have called a "thriller". Also, the romance aspect seemed really forced. I guess it's an expected convention in this type of book, but it was done poorly and i could've done without it entirely. The ending seemed a bit anticlimactic and too "feel-good" for me - I mean the world changed drastically and a whole lot of people died, but it's all good because our protagonists saved the day (eventually) and fell in love? I like my doomsday books a little more doom-y.