blok now uses the Google Gears HttpRequest API to make the synchronization calls to the server if gears is installed on the client. This makes the GUI feel a little more responsive. Next up is using Gears to offload the rest of the syncing work (primarily JSON stringification and parsing) that can be done in gears (everything that does not need to manipulate the DOM.
Joose supports a transparent method to offload hard work into Gears workers that was even talked about on the Google Gears blog. While the method used to be rather basic I'm enhancing it now so that you can use the Timer and HttpRequest api transparently in your code without having to care about whether google gears is actually available (work is done in the main thread if gears is not installed).