ok the thing to realise is that for us hobbyists, there is a point in the technological scheme of things where it already get very good enough for our hobby works. lets call this the "cut off point" - defined in terms of a price limit (the most u r willing to pay) and the best possible specifications that must be available. any further better technical specs will make no real significant difference to your pictures
for me, the cut off point in 1.6x bodies is the 20d. i.e, if i were to take a 1.6x body, the lowest i will go is 20d. things like 30d, 40d, really make no difference to me since the 20d is the lowest ranking item that meets my criteria in terms of picture quality and ergonomical handling. which means, given the current market price, i will not buy a 10d or 400d because they are below my cut off point, i will not buy a 30d or 40d when it arrives, because they are more expensive than the cut off point.
again, why i continue to use the old 1D is because it is my cut off point for pro body. the mark2 is still too costly, the mark3 as well. i can only get them if the price drops further. in fact my cut off point for pro body used to be EOS3 and EOS1n but unfortunately there is no digital equivalent for EOS 3 and i dont shoot film anymore so my only choice left is the old 1D.
what i am trying to say is that instead of aiming for the best, why not cut cost and aim for the cut off point. then what constitutes your own personal cut off point? now that will be for you to decide.
but for my case, i will not pay more than 1.1k for a 1.6x body, thats why i initially recommended you to wait for price drop of used 30d. in fact, why dont you try a 20d now? instead of waiting for the 40d to arrive. honestly, to me, digic II or digic III seriously makes no diff to me (of course it does to you, hehe). and the 20d is still a very nice capable body.