It doesn't matter what class you are or role you fulfil in a raid, RUN SPEED is the best.
The reason for this is that all players have to move during a raid and/or boss fight. The faster you move, the faster you can get to doing whatever job you have, whether it be dps/healing/tanking.
It has been calculated to death - if you spend between 2 and 6 seconds moving a minute (depending on class), then run speed will be better for you than any other enchant. And EVERYONE spends at least that amount of time moving during your average boss fight.
You have three options:
Minor Run Speed (cheap option)
http://www.wowhead.com/?spell=13890Boar's Speed (9 stam, run speed)
http://www.wowhead.com/?spell=34008Cat's Swiftness (6 agi, run speed)
http://www.wowhead.com/?spell=34007Learn them, love them.
The only excuse you have not to have these enchants are if you are a class with talented run speed bonuses that don't stack with these enchants. At the moment, that only excuses assassination rogues and ret pallies.
Kil
