Not sure if its like google talk option or not, but clicking on the top menu in the contacts program (where it says "all contacts"), then clicking "Groups" then select Facebook and it will show all those from facebook (or any other group you added). To see availability, instead of selecting "Groups" at the top it has "ABC", "Availability" and "Recent". So you can change it based on that too.

This doesn't fix the problem i guess, since its more of a filter than a seperation, but least you can filter it, then keep it running in the background for later use.

Edit: Damn beaten