For our Christmas trip, we paid $1125 for the three of us out of Buffalo (Airtran there, Jetblue home....and the overall price above factors in fees for one checked bag per person on the Airtran flight). Flight times are excellent (arriving at MCO at 10:30 am on our arrival day, and leaving at 2:30 pm on our departure day).
Westjet from Toroonto, in comparison, is $1882 for the same dates. Flight times are horrible (arriving at MCO after 11 pm, and leaving at an ungodly early hour of the morning on departure day).
Add in the pleasure of flying from a smaller airport, clearing customs at the border, etc. to the $750 savings and better flight times, and its a no brainer.
We are 2 hours from Toronto and 4 hours from Buffalo, so either require a park and fly for us.