I think it's just a preference thing, and people probably find him attractive for different reasons. In my mind, I like him because I find him pretty good looking and he honetly seems like one of those guys who hasn't let fame go to his head. Especially being in such big movies, along with such huge actors. He seems like the guy you could imagine on the red carpet, but also at the bar just hanging out with the same people he's known for years.
I will admit though, I don't find him to be the most talented guy in Hollywood, or even in his age group. He sometimes seeems to play the same characters in an odd way, but I think he could come into his own. I think I'd love to see him play a bad guy. A lot of his roles have been the semi-young, slightly naive guy. Except for Legolas, who didn't talk much. But we'll get there Orlando. Different tastes, for different people, eh? My friend doesn't get the appeal either.
Style: I really liked his style back when The Lords of the Rings movies were first coming out. It was a quirky back then. The odd t-shirts with all of the necklaces. And word on the not liking the long hair. I loved him during the mowhak/shaved head phase. It really showed of his bone structure.