You can find the new guide here: Cataclysm Resto Druid Guide. ETA: I've posted the guide again to a NEW url, so please update your links and bookmarks!
As ever, I will be keeping the guide updated through changes and patches and adding any additional useful information that arises.
In other Cata preparations, there were a couple of great posts over on the MMO-Champion forums which are definitely worth a look.
Cataclysm Preparation Compilation by tunnland
There is a ton of useful information in this post, from suggestions of what to do before launch day, a full list of the new food, flasks, elixirs, and other buffs, to suggested dailies and their XP rewards to complete before launch day and turn in for quick easy XP at launch. There is also information on loot, strategy, and videos for the new 5-man instances.
What Wrath players need to know to not suck at Cata! by Daetur
This post has some great info for everyone on what to expect in the new Cataclysm dungeons and raids and, in particular, what you need to start thinking about for the changes from the Wrath style of dungeons. There's general advice and more specific advice for DPS, Healers, and Tanks.
As that's quite a lot to look at and read, I'll cut this post off here. Enjoy! :D