I don't see what the appeal is, he seems pretty boring, witty but no different to other witty types through the years.
For me, it's because he's got many of the attributes that I find attractive in a man - sense of humour & wit , intelligence, friendliness, auburn hair, glasses, nice smile, nicely groomed, musicality. One or 2 (or even 3) of those things in isolation wouldn't catch my attention but he's very close to being my 'whole package'.