The Seinfeld DVD releases are now available for pre-order at Amazon.com:

Are you in Canada? Order from Amazon.ca
Are you in the UK/Europe? Order from Amazon.co.uk

Order Seasons 1&2 from Amazon.com
Are you in Canada? Order from Amazon.ca
Are you in the UK/Europe? Order from Amazon.co.uk

Order Season 3 from Amazon.com
Are you in Canada? Order from Amazon.ca
Are you in the UK/Europe? Order from Amazon.co.uk
A release date has been announced: November 23 - just in time for Christmas!
Update: The Region 2 DVD will be released October 25, see UK links above to pre-order now from Amazon.co.uk.
The Season 1&2 set comes on 4 discs, and the orginal full length episodes, 2 versions of the pilot, interviews, deleted scenes, bloopers, outtakes, new stand-up footage, behind the scenes production notes, and an hour-long look at how Jerry Seinfeld and Larry David came up with the idea for the show. The Season 3 set also comes on 4 discs.
Watch the Seinfeld DVD trailer:
Windows Media Player or Real Player.
Pre-order your copy of the Seinfeld DVDs today...or you may not get yours before Christmas. :)