For those that don't know, Xmarks has said they are shutting down shop. You can read more info here: Xmarks Blog
Long story short, if you want to help keep Xmarks running, and you're willing to pay them $10-$20 per year, you can go here (no payment info required, it's a "good faith" commitment): 'I will commit to $10 - $20 per year for Xmarks Sync' - PledgeBank
I know Firefox and Chrome (and now IE to a certain extent) all now have built in sync features, but I know very few people that use JUST one or the other 100% of the time. Xmarks provided, for me anyway, a platform-independent place to store bookmarks, etc., that I could easily get to anywhere, on any browser, and on any phone (using the mobile page). Now that portability and convenience will be locked into one browser, unless I (we) want to go to the hassle of keeping them all synced up manually... what a headache. Not to mention their profile and search features...
So, if you love Xmarks and want them to survive, check out that pledgebank page! If not, ignore me!