Its no big secret that arena isnt working well atm and its stated by most of the wow population.

Its well written here:

http://forums.wow-europe.com/thread....73051425&sid=1

A warlock have NO way to escape a druid who use berserker or a hunter that pops BW.

Reason for paladins,dks,rogues and mages is the top classes is due to having immunity and beeing able to deliver high burst...

Resillience will make things better but it certainly wont save you...

http://forums.wow-europe.com/thread....39774236&sid=1

The guy have 22k hp and 900 resillience, and still dies fast. We all know what happened if you took on a warlock in tbc with soul link and a healer.