This rant fell into another post I was writing, and decided I should post it separately:
As a raid leader, should you still worry about min/maxing classes for raid buffs in patch 3.0.2 (and beyond)? My opinion: Well, why wouldn’t you? You did it before, why should you stop now?
The only thing that is changing is the amount of overlap in buffs now that they will be raid-wide. I am assuming raiding will still have some difficulty scale, and there will be hurdles. There will still be times when you will have to decide whether to bring one person over another. Class balance in raiding will still be important. The difference is that now there is hope of it actually being balanced. No longer will you feel that your raid is at a disadvantage because you could not get a fifth shaman into it, or the third shadow priest, etc.
Blizzard is not making us all the same. They are attempting to make raid composition correspond better to the player base, proportionately speaking, while still allowing for flexibility in slotting. There will not be a single “best” raid composition for any given encounter.
To the people panicking that they can no longer be special, unique snowflakes with the recent changes to raid stacking: get over it! You are oversimplifying the changes as a means of being overly dramatic. Not a single class will be entirely interchangeable with another. Blizzard has been endeavoring to bring a larger variety of talent specs into raiding. If anything, you will now have more ways of being special!