Ok, so I am gearing a fury warrior on WOTLK and I just finished my Shadows Edge quest and I got non heroic Glorenzelg from LK 25 normal as a drop. It might seem like a newb question or whatever but I have a bit of a dilemma...I don't know which one to put in my main hand and which one in my off hand.
Gloren has 895-1344 Damage............Shadows Edge has 872-1309 Damage
Gloren has (311.0) DPS ..............Shadows Edge has (294.7) DPS
Gloren has 3.60 Speed ..............Shadows Edge has 3.70 Speed
What you should be looking at is lowest and highest dmg weapon does, (895-1344 vs 872-1309) as those are the numbers that most abilities scale with.
Slower weapon means that those numbers are bigger when you are comparing 2 weapons of same item level. (gloren is faster, but its 284 ilvl vs 264 ilvl of SE -> increased stats from higher tear overcome SEs slower speed)