Have you thought of saving it to Dropbox or Ubuntu One? You could also try a
bookmark service such as Xmarks which is what many people use. It will sync
your bookmarks as long as the extension is on all your computers.

If the file is in html format it can be read by any browser on any computer.
Firefox bookmarks are already in that format. They are stored as a single
file unlike IE Favourites. It can be found in your
.mozilla/firefox/abunchofcharacters.default as bookmarks.html.