@odyssee, it's a prophecy, mark my words!
I'm kidding, of course, but I really don't see how they'll juggle Maxthon 4, MX Nitro, and a fifth version. Too much effort will be spent into Nitro, not many people will use it, because they expected a full-featured, fast browser. I hope I'm just being a doomsday sayer, but the MX team have always had 2 main versions to develop simultaneously, so I doubt there will be a full-featured MX5 any time soon.