Thanks for the input. There are several I didn't put on there, avant, flock, and a few others.
Not debating, just FYI - Firefox has all the features you mentioned (and more) provided through simple add-on functions. I'd been keeping all my machine's bookmarks "synched" using my own webserver, but with Firefox 3 I switched to foxmarks.
They also have a built-in "de.licio.us" syncher if you're into that. I'm trying it, haven't decided if I like the whole de.licio.us/digg/etc idea, but with de.liciou.us you can share your bookmarks with other people - if that floats your boat, great.
The good news is both the foxmarks and the <span style="font-style: italic">new</span> de.licio.us add-ons works transparently to keep the bookmarks on all my machines synched up. I can do a bunch of work on my desktop machine, then fold open my laptop and a few seconds later they pop up there.
More later...