A few quick clarifications:

Neither Inner Fire nor Inner Will has charges. The decision is on which armor you want up at the time.

Preventing dot clipping is something we want to do in general. It obviously benefits Shadow priests just as much as warlocks.

The idea behind Mind Spike is that you can't always settle into your normal, and high-ramp up rotation. It's also useful when you have to move or get school locked.

The closest analogue to PW:B is the DK Anti-Magic Zone, but it has some important differences, such as a way to counter it in PvP (since it absorbs all damage, not just magical damage).

The idea behind the Holy "cast three in a row" talent (it's called "Chakra") is that we've always positioned Holy as a versatile healer. This talent lets you shift into different modes. If you need to be a tank healer, cast three single target heals and your single-target healing is now better. Cast three area heals, and you can be a temporarily specialized group healer. We're going to try to play this mechanic up with a cool UI to try to get that "I'm almost in the zone" feel. We'll let it apply to as many types of spells as we can, perhaps even Smite for those times when nobody's taking damage.

We pulled Misery because we are pulling every group benefit that improves hit. It's annoying to have to swap your gear in and out depending on who shows up for your group. In general we're going to push even harder in Cataclysm for bringing people you like to play with, not bringing people who have awesome buffs. The answer to almost every question of "But why would they bring me?" should be "Because you know what the hell you're doing."

A few points of clarification:

• We've seen some confusion about Mind Spike. The intention is that you can't always get your full DoTs up on a target in time before it's dead. Shadow priests sometimes aren't sure what to do on, for example, a fight where a boss suddenly spawns an add that you're supposed to quickly burn down and then go back to the main boss. Mind Spike is what you do to that add. As a rule of thumb, if it's going to die in under 15 seconds, then go with Mind Spike. Otherwise get your DoTs up and go into your longer rotation.
• The movement speed from Inner Will stacks with the boot speed bonus. It won't stack with some movement buffs like say Body and Soul.
• We know a lot of people are looking for answers about Lightwell. We're reviewing the talent and spell functionality, but do not have any details to share as of yet regarding its future.