[glypo]

The 50D will replace the 40D... so will be similar price.

Anyway, the xxD range has a very solid 18 month cycle, so the 50D will be released in February 2009, that's quite a wait!

Apart from the better sensor - the 50D sounds very similar to the 40D. The 40D is very capable and if I was you I'd get one. When I got my 40D in June there was £140 cashback which was very nice. To give you an idea, people still use 20D's with great results and they are two generations old... so you should have at least 4 years use out of a 40D before finding a need to upgrade.