You'll be waiting until September if you want it preinstalled. The 2nd gen touch was the first to come with 2.0 or above preinstalled (if you wanted it before that you had to buy a 1st gen and also pay the $10 upgrade fee - some people complained to Apple and got it for free though); Apple will more then likely do that again - offer it for the $9.95 to existing owners, then roll it out preinstalled only on the 3rd gen touch.
And I say September because that's always when Apple updates the iPods.