I was speaking to a guy on the Xbox forum a while back (the guy writes for fightnews.com and is a freaking beast on Rainbow6 & Fight Night ) and he reckoned that the huge delay on the development of Round4 is becaue of Round3 being re-vamped and re-marketed for the release of the PS3.

With the PS3 comming out today in the UK i reckon we wont see Round4 till March '08.