I'd estimate a turnout of 180-220.
(Counted, roughly, ~80 on the BofA corner, 30 on Walgreens, 25 on each of the east corners, and 20 or so on the bridge, though the latter could have been migrants from the already-counted main body. )
Other estimates (and stories): 250 (The Union), 300 (Yubanet).
From the bumperstickers and faces, there didn't appear to be much overlap with the Tea Party contingent. Signs were pretty much as expected; "Visualize local banking" was the standout.
It's not clear what the BofA folks thought of the whole enterprise; with the usual 20-20 hindsight, I suspect that would have made for a great soundbite.