I honestly don't think Alternity could have happened in any format other than the one it did, really! There are some long-running, broad-lensed fantasy epics out there, but the journal/RP format gave us just so much room to roll around in, and it let us fully explore things that would have been excised from a novel because they were too much of a digression. (There was a lot of stuff that looked like a digression at the time and then was revisited later!)