I've got to disagree about the pike being better.

I have the Sword with a +16 str gem.

So, I have equal Str, less stam (as DPS I could care less), and 81 crit.

I'll take the extra 10 crit any day over some Stam for my Unholy DPS spec.

Actually, as said above, the sword is easily better than the Axe. Sure there is a raw DPS increase, but if you're actually running 2handers you're not worrying about white damage as much. Sure it could be ~20% of your DPS in a raid setting, but what about that other 80%? The bulk of your DPS with a 2hander is coming from strikes and skills.

Axe
low 507, high 761, str 90, agi 54, stam 94, haste 90, crit 0

Sword (with +16 str gem)
low 514, high 772, str 86, agi 0, stam 105, 0 haste, 81 crit

The sword will always have higher base strike damage, minus stats, due to the higher base damage. Adding a +16 str gem into that red socket gets you nearly the same str as the axe. You do lose 4 str, which is 8 ap or .57 DPS. The 8 AP loss is pretty somewhat marginal, and insignificant for strikes with this weapon (the over/under increase of 7 to 11 in base damage will trump even a 1:1 AP to damage coefficient).

The sword has more stam and trades crit for haste. I think there are more than enough posts that decry haste for DKs. Sure it does actually contribute to DPS (which something like, say, MP5 wouldn't at all), but the effect is pretty small, especially compared with crit.

Hands down, if you're using a 2hander for DPS, the sword is better. We aren't Rogues... so the DPS number on the sword is mostly meaningless. I'd say the axe is actually the dark horse... worse base strike damage, no sockets, haste over crit... and it has agility on it... ick.

Don't forget the 40 something points higher top dmg for every single strike you do.