One thing that annoys me about autosyncing is that it is triggered too soon, or too often, and that while running it locks up Firefox for anything between 2 to 30 seconds (sometimes more). Especially when writing a note or tagging a newly added item it is quite annoying to have Firefox become unresponsive just because Zotero is trying to sync that new piece of information.

Proposal: implement a longer delay before autosync hits in after (1) adding a new item; (2) adding a tag to an item (more tags will often be following); (3) adding a note to an item (note-editing will often be following); (4) editing a note.

(I recognize the potential problem of (4), as a user may have a note field active for a time that is much longer than he is actually editing it. This is why I recommend a longer delay before sync kicks in rather than putting off sync entirely until the note is no longer edited.)

A potential other cue to delay autosyncing would be keyboard input anywhere in the Zotero window, but I don't know whether there are potential downsides to that. It would certainly solve my common problem of adding-then-editing a note and having to wait for my keyboard input to show up because -sigh- Zotero is autosyncing the note already.