My buddy has a rogue and he stumbled upon an amazing website for Rogue gear (shadowpanther.net) I think is what the site was called. Anyway, it calculates the most important stats on a scale and takes all gear into account (raid, pvp, quest, bop, boe) and scales it best to worst, for every slot!

I can't seem to find one for a Mage though. Does anyone know where I can find a tool like this? Thanks!