I've been using XMarks for a few months now, after having tried different options (Firefox sync, evernote, instapaper) and haven't felt the need to use anything else as well. It can synchronize painlessly between my various computers and has different profiles (subsets of folders) so that you can differentiate, for example, work bookmarks from personal ones. There are plugins for all major browsers (I'm mostly a Firefox user but sometimes use Chrome) and a handy web interface.
It also has a nifty backup service allowing you to restore previous versions of the bookmarks, should you have erased something important or something else. There are also other services (password sync and open tabs sync) which I don't use.
I use it to store ~2000 bookmarks in a loosely disorganized set of folders. My biggest grief is that Firefox's bookmark user interface is terrible (and Chrome's only slightly better), and it becomes painful to use when you want to classify hundred's of bookmarks.
It also has a nifty backup service allowing you to restore previous versions of the bookmarks, should you have erased something important or something else. There are also other services (password sync and open tabs sync) which I don't use.
I use it to store ~2000 bookmarks in a loosely disorganized set of folders. My biggest grief is that Firefox's bookmark user interface is terrible (and Chrome's only slightly better), and it becomes painful to use when you want to classify hundred's of bookmarks.