Optimistic version control systems like CVS and Subversion allow people to decouple their work: instead of simultaneously editing the master copy of a file (and stomping on one another's changes), each player changes a local copy, then merges it into the repository. In contrast, most ticketing systems still use the "everything's on the server" model: there's no notion of a "local" copy of the ticket database.
But Google Gears has got me thinking: could we build portals like SourceForge and DrProject on a "write then merge" platform? Would it improve performance? Scaling? Usability? Or is it just a hammer looking for a walnut? Any MSc students looking for a project out there?