Although I am loath to admit it, it looks like left candidates in general are going to have an uphill battle in 2010 due to the popular perception that Miller was a mediocre mayor. I write this with the fresh memories of Michael Thompson getting plenty of free airtime this week by blaming the municipal government for the swine flu vaccine debacle.
Outsiders like Murray may fare better than Miller's cabinet, although I think even Murray would be forced to put some distance between himself and Miller by virtue of the Miller Derangement Syndrome that is rampant in our city. I think it makes sense for Giambrone (and Carroll, for that matter) to take a pass on 2010; the lack of an incumbent would force Giambrone and/or Carroll to defend against anti-Miller strawman attacks that would surely prove fatal to their chances given the lack of sophistication of our political discourse.
On the right, I can't see anyone other than Rob Ford breaking ranks to compete with a consensus candidate like John Tory or Michael Thompson. If Tory decides to do what he does worst (i.e. seek elected office), Thompson, Stinz and Minnan-Wong may run, but their real goal is to raise their profiles for 2014 while harbouring a secret hope that they can pull a David Miller and break through a disjointed field if the race unfolds in an unforeseen manner.
Giorgio Mammoliti is a bit of a wildcard, having bounced around the political spectrum somewhat since his early NDP dogmatism. He may also see himself as a Miller-in-waiting, but I think he lacks the power base to make a serious play.
That leaves Smitherman, who clearly fancies himself the frontrunner if only he could find a hacksaw to cut away this e-health scandal cancer that seems to have metasticized to him. He seems to be enough of an insider that he won't be allowed to take the chance of losing; if he runs, he will probably have set up the appropriate fall guys and positive media agenda to minimize the e-health blowback.
In terms of longshot outsiders, I notice early in the thread that Rocco Rossi's name has once again been trotted out. This as-yet-unfired Ignatieff lieutenant certainly would have access to the financial backers necessary for a relative unknown to mount a grand coming-out party, but such backers would also need to feel the love reciprocated by the electorate in short order or Rossi's would be a short-lived candidacy.
My safe money is on Tory, but I would also put some money on Thompson to cover my losses when Tory literally implodes into elementary particles during the first debate after pulling a Kramer and hurling racial epithets at Michael Thompson.