Since I've posted in all the other polls today, I'm trying to get to this one as well. Before voting though, I'm trying to get caught up by reading the actual TI proposal thread. Once done there, I'll be back to cast some kind of vote here...
Edit- Alrighty. I've finished reading the basics on the Transitive Isles and the Proposal thread up to current. (Didn't follow all the links for super detailed info on all subjects. Don't have time currently for anything but the Reader's Digest version.) I can say that it looks totally playable to me. It's got places for everything I can think of including the far off Allaria (POL setting on bigger continent) for those that want that. It's also open enough to add in anything anybody could want with just the effort of saying a new island has been found in the shifting seas.
There are minor quibbles of things I'd do differently, but that's to be expected as I didn't write it. I'm not gonna gripe or complain though because it's easy enough for me to use what's there and modify as needed in a specific locale if I need to for my own adventures.
So I give it a big "YES" from me. Lotta good work in there from everybody. Now I just gotta figure out how to work Wiki things for stuff like the character records and such since that's gonna be important.