Earlier quoted context omitted.
Right - but I am curious about how Stashmarks handles conflict resolution, if it does. I naively assume it simply de-dupes URLs, meaning unexpected things could happen with multiple Chromes that aren't running sync or have updates queued while working offline. Please correct me if I'm wrong. (I also agree with the comment below that it's an edge case for most users, especially Chrome sync users.)
URLs uniquely identify bookmarks, if two chromes have a bookmark with the same URL but different titles/tags, stashmarks will show whichever was synced first.
If I edit a URL, stashmarks doesn't reflect the change in the UI, at least when the original is still pending download. Looks like it's actually changed internally.
Also, I can't delete (or edit) a bookmark in stashmarks that I no longer have saved in my browser. Recreating it and deleting that does nothing, even when logged out and then in.
Hope these critiques are helpful.
Clearly, these are all edge cases, and overall your service is impressive.