Rated 5 out of 5 stars

Awesome addon !

Since i'm also a user of greasemonkey, and enjoy having my prefs sync'ed through different computers, I'd like your help to implement such functionality for different files.
Oh ! Also it would be awesome to not sync stylish prefs, but usercontent.css, userchrome.css and prefs.js, since everything can be done without any addon (probably implementing adblock/trueblock and noscript)...
Thank you in advance for your help

This review is for a previous version of the add-on (0.1.2.1-signed.1-signed). 

As I mentioned, I'm not using GreaseMonkey. But Stylish Sync is open source (https://code.google.com/p/stylishsync/), so feel free to port it!

Preferences from prefs.js can easily be synchronized by adding or editing corresponding about:config-entries (services.sync.prefs.sync.*).

userchrome/-content.css are single files which can easily be ported and modification to both files requires a browser restart, so synchronization is only semi-useful.
And since I've been using Stylish, I didn't touch any of those two anymore, because it makes testing without restart so much easier.