So my ret pally and my resto druid are fun in pvp. Prot pally is not. Feral druid and balance druid are not. Khour and Moon have two level 30ish toons they are playing and ONLY leveling in battlegrounds. I'm thinking I'm going to level my mage Susanin this way. First catch her up to them and then level in BG's. Use the pally and druid to farm stonekeeper shards and buy stuff for her. Etc.
Except there is kind of this debate between me and them. I think that my level 35 warrior would be just as useful in a bg to their Shaman, Lock team as the mage. I mean sure the mage has the AoE ice freeze and sheep and slow on -everything- icy she casts... but the warrior has charge/intercept/stun and an AoE fear and can remove fear/sap/incapacitate via zerker rage.