It's not that much of a stretch that they could reform - and contrary to popular opinion, I believe they do get on.
According to wikipedia; Clarke was supposed to remix Moyet's '94 song, "Whispering Your Name" and with Erasure, Clarke and Moyet tried to record her single "This House" as a duet. This project never came to surface, because Sony Music Entertainment would not permit it.
I really hope it happens!
Some further digging has turned up an official Yazzoo MySpace page;
http://www.myspace.com/yazooofficial