Potent Noble Topaz

Very good for balance druids too, since they get excellent scaling on crits when you account for both Vengeance (100% crit damage bonus instead of 50%) and Nature's Grace (0.5s casting time reduction on next spell after crit) talents.

In general it's better to prefer lots of gems with multiple stats rather than gems with single stats, as the total stats you get out of your gems will be higher... just so long as they're all useful stats ;)

One of the best gems for crit mages. Seems the points shared in crit + spell damage make up more then a flat +crit gem.

You only need to stack hit if you raid. Some of us have raided in the past, and no longer choose to do so. You need *very* little hit on your gear for heroics. And odds are, you'll have a harder time getting rid of excess than you will making sure you have enough.