Well, I admit that sometimes I just sit on a rocking chair in front of Exposition Hall in Town Square, and just watch the characters rotate in and out! Sometimes they replace themselves with themselves: for instance, Pinocchio and Geppetto go inside, and five minutes later they come right back out. Sometimes the characters switch off with another group of characters, like Horace and Clarabelle go inside, then Chip and Dale come out, then when Chip and Dale go in, Horace and Clarabelle come back out.
But yes, if you walk by Town Sqaure at, say, 9:20, then come back around 10:45, you may see some different characters out. But like others said, the characters don't seem to differ much right now. It's usually a group consisting of characters like Pinocchio, Geppetto, Foulfellow, Gideon, maybe Daisy, Chip, Dale, Horace, Clarabelle, Pluto, maybe a couple of other commons. (Horace and Clarabelle are pretty new and unusual to meet, though!) There used to be much more variety in Town Square, but right now there isn't.
