I've got THE MUMMY RETURNS on DVD which features a trailer for THE SCORPION KING and to be honest it doesn't look too bad. Of course, it was only a trailer (which are designed to make films look good) and wouldn't be the first time a trailer would be better than the actual movie, if THE SCORPION KING turns out to be crap.
According to the rumours page a possible title for The Mummy 3 could be THE MUMMY RETURNS AGAIN (but it's only a rumour). I still haven't heard anything about a cast, storyline or even a production team. I hope they all come back to do one more though (especially Brendan Fraser, he rules). If no one from the original films want to do it then it would be a waste of time even bothering. I hope they all return.