Many have been waiting and speculating as to Wesley Clark's intentions to run for the presidency. Certainly he hasn't lept into the (extremely early) fray... but at the same time, he's been hanging around the edges of it. Many take this as evidence he's biding his time.
But perhaps he's casting a wider net than the presidency. Unlike all the other favorites he's been out of a job for some time, and probably wouldn't sneer at the #2 spot, or at least Secretary of State or Defense. Such positions befit an Executive-branch politician like Clark, but were unavailable with George Bush in the White House. However, all indications point to a Democratic victory of one sort or another in 2008. And to get those kind of jobs, you need to make friends and earn respect during the campaign, not enemies. And that is the sort of tack he's taking.
I'd say the same about Gore, but having already been Vice President it wouldn't make sense to accept anything less than the Presidency or Supreme Court.