I think at most DKs will only get some sort of vampiric damage-heals, considering they can TANK without a shield (one of the class panel points). But knowing Blizzard, nothing is finalized.

The unveiling of WotLK also seems rushed. If you look at the expansion website, they say that the introductory cinematics are not yet complete and will be ready at a future date.

Personally, I feel Blizzard is pushing to get SCII out and rollout their other unannounced title as to smother Warhammer's buzz pending this Fall or Winter. Knowing EA's marketing, they will likely release before the end of the year regardless of market conditions.

If Blizzard can keep a series of exciting announcements and releases rolling, WAR will be in serious trouble to live up to its promises of a WoW-crushing debut.