Thankfully, "Scrubs" is owned by Touchstone, not NBC, so they'll probably release it independent of the season premiere (which could be an early replacement for a bomb, or could be in January). Season 1 was only released two months ago, which probably means it'll be a while before we see the next set.
I too would love to see Arrested Development S2 be released onto DVD before the new season starts. I watched S1 on DVD exclusively, and then became a die hard season 2 devotee.
But the lack of announcement has me worried. Hopefully TPTB will coordinate this. Until then, you might want to check out http://getarrested.com/
Just checked DVD aficianado no set release dates for either season 2's, but they are up like they are awaiting release dates, so hopefully we should know soon!