I knew this was coming when I asked Peter in the Fox Chat earlier this year and said he was working on it and it should be alot of fun. Since then i've heard all kinds of rumors nbout when it was coming etc etc but today I read what was sorta of official confirmation but not close as Fox hasn't officialy announced it.
Here Katie O'Connell who is involved with Imagine Television (the company that produces the show) had this to say.
Q: Can you comment on when we’ll see a DVD release of Arrested Development?
A: Hopefully, late summer.
If this is the date then this is better what I thought as I assumed possibly September or October. And it's also true what they say this year this summer is the best for TV Shows on DVD.
Here's the official link.
http://the-op.com/view/article.php?sect=2900&a=37