User Sync on Multisite Install

I would like to see the user sync plugin work so that if a user signs up for one site on my multisite network their user information is entered into the user databases of all the network sites automatically. Currently, as i understand the user sync only works across seperate wordpress site installs.

I would also like to see an option for the user sync to automate every time someone signs up for a subsite on the user sync network.