Who deserves it more this year? Alonso, Webber, or Vettel? Short answer: They all do.
Personally I'd say Webber most deserves the championship because he's worked so hard for so many years, stayed with a start-up through the worst, and finally sees a fruitful season. If he doesn't get this one he may very well never have another shot.
BUT, in this business there is no such thing as who deserves it more, only who's more dominant, more consistent, and more....... lucky. Yes it's better to be lucky than good sometimes, umm... all the times. Any of those on top now will need all three qualities to claim the most sought after prize in all of motor racing.
Good luck to them all!