Don't get me wrong, with Denver out of the running, I want Dallas to win. Kidd, Nowitzki, Stojakovic and Terry are all probably on their last chance to get a ring, and I like all those players more than LeBron. They get extra props for dismantling the Lakers.
I just don't agree with the party line about how LeBron conducted his affairs. I'm not talking about as a basketball player, but as a public figure. I watched the '10 ECSF, and he had a bad series. To you that's "quitting," to me it's "having a bad series." His departure from Cleveland was a media event for TWO YEARS before it happened, and I have no problem with him announcing his decision in a public fashion.
If he'd gone to, say, the Lakers I would've been upset, but hey, it's his decision. That's what free agency MEANS.
On a scale of "sports figure assholery," LeBron is about a 2/10 - personally arrogant and a showoff in a playful but nonetheless mocking manner.