A popular idea is to use TW as a type of groupware. Unfortunately, out
of the box TW has no way of dealing with concurrency issues. Its a
stand-alone application.
There's TiddlyWeb if you want to pursue that.
One idea that's crossed my mind is to use the Include plugin:
http://tiddlywiki.abego-software.de/#IncludePlugin
Assuming a shared intranet, assign each user their own TW, which they
can save to. Each such TW would be set up to allow viewing of the
other user's tiddlers via the include list. Everyone would follow a
naming convention, including perhaps their initials in each post. Like
[[Test 12/25/2009 Do Reindeers Fly #16 OSN]]
Where OSN would be the initials of the participant (Old Saint Nick).
The initials could be built into the "new tiddler" template as a
reminder.
As long as this is a trustworthy, cooperative group this might work.
It avoids issues of concurrency, synchronization, and name-space
collision that vex even full-fledged groupware.
Mark