For what its worth, back when Chizen was at Adobe the statement was made that release cycles were every 18 months. They are totally opposite of Apple and give as much transparency to the investors as to their roadmap. (or did)
So that would put us at around Oct, I suppose for an update by the Adobe group. Yes it may feel like its a 2 year release...not far off...especially with macs coming out at a faster rate than Adobe products, but it would seem this year you will hear the announcment (around Oct) of CS4.
It has been out since what, April of last year?
Tell you what...wait and you can get CS4 with Nehalem Macbook Pros. 😉
(Which basically have the frontside bus eliminated from it...sound cool? You bet!)
peace
dAlen