Sephyx's TheoryCraft 2 places everything you need to know and remember about your spells right on your tooltips...or if you're using the default action bars, on their buttons. It could also let you compare any gear set you wish.

It has an ui interface for comparing the dungeon 1, 2 and tier 1 and 2 gear sets to your current gear, or any combination of gear you wish. Just click the button, have a look at your new stats and hold your cursor over a spell to see how much more/less damage you would do in that set. Talents can be tested in a similar way.