The premiere of Chappelle's Show season 3 has been pushed back on Comedy Central, and the release of season 2 on DVD has been delayed because of it. A new date hasn't been set, but we should hear something when the premiere date for season 3 is locked.
Companies often look for ways to get more press for their titles, and releasing the previous season of a series just before the new season provides them with more opportunities to market the DVD release. We often see delays of season sets due to delays of the new season, with 24 Season 3 and Sopranos Season 5 being two recent examples, though the delays of both shows were planned by the networks. Chappelle's Show Season 1 remains the top selling TV-DVD for 2004, and holds the top spot ever according to distributor Paramount Home Entertainment, beating out The Simpsons a few months ago.
We'll post news when a new release date is known.