Surely not long now until we can throw GT5 Prologue in the bin, and start driving around in the new game... 
I've been eagerly anticipating the game, of course. I wouldn't say "not long", however, since I still haven't seen any meaningful release dates. All I've really seen is either "TBA" or generalized speculation along the lines of "TBA 2009" or "Q4 2009". Being nearly the end of September with no definite date slated, I'd be mildly surprised if it releases in calendar year 2009 at all, and more expect it sometime in early 2010. So, it's likely at least a handful of months off yet. At least I'll have Forza 3 to hold me over until then.