Originally Posted by Groucho 
That's a very unfair comparison. Not only the 50mm F1.4 vs F1.8 (the Canon F1.8 certainly can't compete with the Pentax 1.4 on any level), but an F4 long zoom vs an F2.8 one? Two third-party lenses for Canon vs zero for Pentax? And to be completely fair, you'd need all IS lenses on the Canon side - which means no 50mm and not the Tokina 16-50mm.
You can work prices any way you want and you can certainly build a K20D system for the same or less than a comparable 40D.
Not to mention that the Pentax DA*'s are weather sealed, so you'd have to go to Canon L glass for that, and the 40D isn't sealed either, so up you go to a top end body.
May not matter for a lot of people, but Pentax weather sealing is a massive plus for me living in tropical area.
There's no way I could afford to buy weather sealed Canon or Nikon gear!