I also just updated to v. 10.0, and notice that Firefound is once again compatible. I don't think it worked with the previous version of FF.
Firefound helps you locate your missing computer, and remotely erase some data from the hard drive if necessary.
Howevery, Firefound is slated to shut down on June 1, 2012. See
https://www.firefound.com/. Its author recommends Prey (preyproject.com) as a replacement.