With 9 others from my guild, I went and killed 5 bosses that were open for beta testing over the past two days. I did them all as Resto. I will try to get longer comments out at some point, but, here's a video of one of the more fun fights:
YouTube - Cataclysm Raid Test: Bastion of Twilight, Twin Dragons

Very briefly:
--Still healing almost entirely with HoT's and instants.
--But mana is a factor. You can see me pacing myself through the fight.
--There's...

• Hamlet

I haven't seen anyone else comment on this, but it seems level-based partial resists have gone away in 4.0. Previously, all spells lost 6% damage on average against a target 3 levels higher. But, examining the log of the night I raided as Moonkin this week revealed no evidence of partial resists, and I didn't observe any shooting at a level 83 target dummy for a few minutes.

Best I can tell, that mechanic is gone.

• Hamlet

Just a quick list of potential bugs I can think of. I'll add more as I think of them or people remind me and then try to send them to Blizzard.

Balance:
--Sunfire has a 3 second tick rate before haste, as opposed to the 2 second tick of Moonfire. This makes a single Sunfire cast weaker than a Moonfire cast (in other words, the Sunfire talent currently brings a DPS loss).
--Entangling Roots is not affected by Moonfury damage bonus.
--If Shooting Stars procs while...

• Hamlet

I just logged to Cataclysm beta (current build 13189) and confirmed that the IS and Moonfury reductions are not present there. IS is doing twice the damage it's now doing on live, and Moonfury is giving 25% to all spells.

The recent beta patch notes ( MMO-Champion - Cataclysm Beta - Build 13183 ) were all easy to verify, including that Starfire has had its cast time reduced without a corresponding change in coefficient. Only exception is the Moonfire note--I can't see any change...

• Hamlet

As many people have noticed by now, a number of hotfixes went in after the first night or two of 4.0 raiding, to adjust the wildly disparate DPS values of some classes. I spent a long time last night retesting essentially all of the Balance spells to see how they'd been affected. Here are the results:
--Insect Swarm base damage and coefficient reduced by 50% (122 base damage per tick, 0.13 coefficient). This one many people noticed right away.
--The other big one: Moonfury is now...

• Hamlet