My Bet
Rather than right a whole long post about it, I just thought I'd like to go on record early as saying I think John Edwards is probably going to win the nomination. If I had a choice between leading in national polls (Clinton), leading in fundraising (Obama), or leading in Iowa (Edwards) I'd take leading in Iowa. Money has diminishing marginal returns and Edwards has "enough" fundraising to keep running a major campaign. National polls, meanwhile, can move a lot in response to what happens in Iowa, whereas Iowa doesn't move in response to what happens nationwide.
Last, the emerging Obama-Clinton dynamic is making it very likely that Edwards can keep plugging away for the next six months and become everyone's second choice.