I know I'll have something of substance to think about.

In this case, I'm thinking in a lot of different directions.
I'm thinking about your question. About Obama. And about the term "progressive."
The problem with the term "progressive" is that it can be spun so many ways, depending on which definition you choose.
At it's core, "progressive" means to move forward, to make progress, with an agenda. It doesn't have to be a "liberal" agenda. Conservatives, and fascists, can be "progressive." The DLC, the conservative/corporate wing of the Democratic Party, has a think tank: "The Progressive Policy Institute." Whether you consider that an Orwellian use of the word or not, we might be able to agree that their goals are not traditionally "liberal" or "left."
Then there's the common assumption that "progressive" is a politically correct version of the abused "liberal." I don't think this is particularly accurate at this point in time. Plenty of progressives are not particularly "liberal."
In that case, Obama can be fairly called a "progressive," even though he's clearly not a "liberal." The casual use of the term, without specification, is much like his campaign. It uses all kinds of terms that lead people to envision something that may or may not be what he intends. I think part of the problem is that some people who voted for him in the primary thought they were getting a
liberal progressive, rather than a PPI progressive, despite the number of times it was pointed out to them. Now they are experiencing voter's remorse.
I don't think there IS unity within the "progressive" community. We've seen "progressives" that are willing to sell liberal principles, and even Constitutional protections, down the river for Obama's sake. And, of course, there are others that are less willing, or not at all willing.
A look at Obama's history is instructive. You refer to him as a "progressive community activist" early in his career. This, too, leaves me wondering: do you mean he was a liberal/left community activist, or the same kind of progressive he is now?
You mention his need to change. Did that "change" mean learning to work the system, instead of fight it? Did it mean adopting centrism as a vehicle to "progress?" It surely meant learning to fight "dirty," as he did when he challenged petitions to nominate all his challengers in 1996, clearing the ballot of any challengers at all, including the liberal activist Alice Palmer.
I see that he has the political skills to win an election. The big question is what, exactly, will we be achieving with him in the White House? Will we get someone who puts his obvious fighting skills to work for actual liberal/left causes? Or will we get someone who, in guise of "working with" republicans, gives away the issues? We've seen more compromise than fight on issues since he hit Washington. Why would we think he will be different in the oval office?
As president, he'll have to show up to sign or veto everything that gets sent to him. No skipping the tough votes, a reputation he gained in the Illinois Senate, according to David Ignatius.
Obama is not a win for the liberal left. At best, there is a possibility for guarded cooperation. That's certainly more than McCain offers, of course.
It's also not enough to earn the enthusiastic "trust," the blind faith, that some of his supporters are pushing for.
The real question I'm left with is this:
To use your metaphor, just WHO is fisherman Obama tossing worms to? Some would say he's fishing for centrists and republicans. Some would say he's luring liberal/left votes with the deliberately vague "change we can believe in," which can of course be shaped to the differing beliefs of each person who hears it. Who will end up gutted and fried in the process?
Time will tell.