I noticed the same thing...today's bikes offer a better build and frame for less money than 5 years ago, and you're right, theres a lot of choice at $700 cdn.
I was very impressed with the new Marins this year...I have an old Bobcat Trail that has taken a lot of abuse over the last 6 years, and the new ones have a better fork, disc brakes, and that remarkable Marin frame (with a 10 year warranty)
Trek, Specialized, Giant, and Gary Fisher (now Trek) have some great bikes at this price as well...I haven't been too inpressed with Cannondale since they went into Chapter 11, and the low end Konas are definitley low end...both Kona and Cannondale seem to offer a cheaper build when compared to their competition at the same price points
Happy hunting...its always the fun part