USAir/AA is not my airline of choice any long either. I am guessing the biggest reason for the price difference you referred to would be the UAD to CAD exchange rate?

Delta is my airline of choice and I would think they would have something decent from DTW. Their miles/rewards program is much better than AA IMHO.

Honestly, for this year, $697 USD is not a bad price as I paid more than that on Delta. Unless you are in the NYC metro area, there are not a lot of good options other than living near a hub city.