Sync of bookmarks across platforms

The creators of "Foxmarks" for Firefox, the bookmark sync utilitiy, finally have the beta releases out of Foxmarks for IE and Safari. I have the beta of the IE release, but signed up too late to get a beta spot for Safari. Good news, they hope to have the release candidates ready in just a few weeks.

So far, auto-sync from Windows XP to Vista to Mac to Ubuntu Linux to Linux mint has been flawless, between IE and Firefox. Not even a hiccup. It looks as though it may finally be possible to auto-sync favorites and bookmarks across multiple browsers and OS' without all the cloak n' dagger, dog and pony shenanighans it's taken before

Boy, that's great news. That's the biggest hassle about using multiple browsers. Can you choose which is the primary browser or does it have to be FF or doesn't it matter (ie they all sync to each other regardless of which you bookmarked on) and here's the biggie: is the catalog structure maintained across all platforms?