Sorry forgot about weapons =).  Enhance wise while it is funny to watch someone try to cast with Dual wield wf on some 1.8 speed weapons, for a serious raider, 2 slow weapons are best. Preferably  about 2.6 speed and yes Windfury on em still beats any combination atm.  As for elemental, just get a spell damage weapon unless you are pvping, get a very fast weapon and use Flametongue. The damage co-efficiency from spell damage isn't fully balanced and favors fast weapons. (in response to a few questions above)

I was Enhance from 10-58, elemental from 59 to 70 and i switched at 70 to enhance again, just to c how it is to melee..It cost me 500g (ouch) but thats another story! What i want to say is that as an elemental in PvP, i used to kill ppl in 2,5secs (chain Lightning + frostshock + overload, all crits) from 36yards. it didnt happen often, but when it did, it was worth it! As an elemental, i used Frostband in my weapon as it gets from our +spell dmg and it crits, meaning i used to hit for 100dmg with my weapon +700crit frostband! And it gave a nice additional slow debuf, while frostshock was on CD. As Enhance on the other hand, i liked the fact that i scarsely ran out of mana (usually i out of health first!) Also, i noticed i could deal with Locks and their felhunter with greater ease!
In conclusion, the decision is up to whether u want to hit from >5 yards or from >36. The dmg from enhance is a bit better, but i m paying the price with my often deaths. In elemental, 36yards give u a lot of time to do many many things! And ofc, as enhance so far, wf is the best in Dual Wield, as i has seen it proc with Stormspike, meaning i did like 8 hits in one second!
BTW, the best talent tree for Ele PvP is 40/0/21 (insta chain = death ) and for Enhance PvP is 15/46/0, faster Shocks upgrade ur dps a lot. (dont take clearcasting in ele as enh, it doesnt stack with Focused of enhance, so its a waste of talent point)