The Washington Post and New York Times report on the group of old, increasingly irrelevant moderates who seem to want to draft Michael Bloomberg for a "national unity" government. There's a serious problem, however. Neither Bloomberg nor the people trying to draft him have a national constituency or an actual issue-based rationale for running.
As I've written before, the only people who want Bloomberg to run are (a) moderate former elected officials and pundits who want to be relevant and dislike polarization and (b) consultants who would make a fortune from his candidacy. To repeat my line: some people call pundits and political consultants the elite; Bloomberg calls them his base.
The reasons Bloomberg is exceptionally unlikely to win are straightforward. Third-party candidacies are usually built around an issue that cuts across party lines like the deficit or race; Bloomberg has no such issue. More importantly, the factors preventing a successful third party bid -- which include strategic voting for one of the top two candidates, party loyalty, ballot access, and the Electoral College -- are essentially insurmountable. As a result, Bloomberg would probably follow the trajectory of John Anderson, a moderate Republican who ran for president as an independent in 1980. He entered the race with a splash and then tailed off into irrelevance. I would expect Bloomberg to do the same thing despite his billions.
With that said, Bloomberg would undoubtedly affect the race, particularly if he used his cash to go negative on one or both major party nominees. My take is that he would be more likely to peel moderate Democrats and independents off of, say, Hillary than to pull voters from the Republican nominee. But it is hard to predict.
In the end, he's more likely to pull a Colin Powell and flirt with the idea for a long time before finally saying no. You get a big ego boost without the humiliation of utter defeat. (Ask Fred Thompson what happens when you say yes!)