Looking at the topic I was guessing (rightly) that some cool-headed fella will say "the one with the most points at the end deserves it".
Like we don't know
Anyway, in terms of ability I think we've seen why Ferrari has signed Alonso in such a desperate manner. He has delivered (albeit with obvious biased support from the team over poor Felipe) and with a somewhat inferior machine is currently leading the championship. I think my "logical" vote goes to Alonso.
Emotionally, though, I don't like this guy and I don't want to see him win!
That said, I don't think anyone else "deserves" the title this year, honestly speaking. Personally I'd prefer Mark taking it but my gut feeling is that he is somehow not destined to be a WDC. Just like Massa.