It's based on a thread posted on Woohp.org http://www.woohp.org/forum/index.php?showtopic=14644
It would be fun to see Britney again as well as a team-up of Tim Scam and Geraldine.
Also, rememberAriel from season 2 episode "W.O.W"? She said after the first confrontation with the Spies then she'll return for revenge and it'll be cool to see a 2nd round between her and the Spies. We're still waiting...