A fellow guildie and paladin Anzak have been treating the guild (Initech) with his adventure/findings in beta. Since I have not been invited into Beta I use him as a resource with any questions I have about Wrath.
His recent entry, he mentioned the Sunwell dailies are still active in the current version of Beta. For some reason I find this odd and I believe Blizzard may remove some upon the release of WotLK.
However in Beta’s current state all of the dailies are active and give a decent amount of gold with a very nice amount of XP. I’m not sure of the exact number but Anzak said the XP is noticeable. If Blizzard leaves in the dailies, I can see myself incorporating Sunwell dailies along with the Northrend quest in my daily routine. Especially when the dailies on the island only take me 45 minutes to complete. Plus Sunwell dailies provide an alternative area to level because the first week(s) of Wrath will be hectic.
Also worth mentioning, incorporating Sunwell Dailies to your questing can potentially leave more quests open when you hit 80. This will in turn provide you the full gold benefit of the quest at level 80.
It is something to think about.