Classroom Salon

 Salon falls short of something like PBWorks as a composing space, for two
main reasons.  First, the composing tools just aren't there yet, because
they're not a priority (yet) for you. Second, Salon doesn't really have the
whole page history element or the ease of tweaking text at the line level
by toggling back and forth between edit and view (yet?).

 Where Salon easily outdistances both wikis and any learning management
system like Blackboard are in the very areas where I'm using it this
summer:  as a hub for classroom readings and annotations (and, at your
suggestion, for peer reviewing).