Blood Elf.
The AoE silence may not seem awesome at first when you have mind freeze and strangulate, but it is simply awesome for arena.
I love to Mass Death Grip + Arcane Torrent right after. It serves as a silence and an interrupt. It is simply murder to any caster based team.
Mind Freeze is nice, but most have it on a 2.5 second round robin on current target. Strangulate is awesome, but costs a rune and 2 minute (1 minute talented) cool down.
Arcane Torrent does an AoE silence and gives you 15 runic power. It is off global cool down. You don't have to worry about resources, gcd, or direction. It makes going after healers a lot easier.
Just be aware of diminishing returns.
http://www.wowwiki.com/Diminishing_returns
The first target will suffer a 2 second silence. If you use it again within 15 seconds, the targets will suffer only 50% of the affect (so 1 second). If you use it a third time within 15 seconds of the last one, the affect is 75% (so 1/2 second silence)
You could make a sequence in IsBoxer with the appropriate delays, to lock out a caster for 3.5 seconds - almost as good as a second strangulate.
Strangulate will lock out a caster for 5 seconds (7 seconds if glyphed and they were casting at the time).
