Canon 40D:
Pros:
- Excellent photo quality (with a decent lens attached), with nearly no noise;
- Rugged, well-designed, weather-sealed body; Cheaper than the competition, especially the D300; Huge 3-inch LCD with live view feature; histogram and composition grid available; Shutter release noticeably quieter in live view mode; Dust reduction system; Full manual controls, including lots of white balance options; RAW format support, and in two sizes; good editing software included;
- Very quick performer, especially in terms of autofocus; Best-in-class continuous shooting mode
- Custom spots on mode dial + user-defined My Menu; above average battery life; Remote capture software included; live view available in software;
- Tons of accessories available, including a battery grip; Optional (but expensive) wireless transmitter
Cons: Tends to underexpose a bit; Some redeye; Live view not available in auto/scene modes; UDMA Compact Flash cards not supported; LCD pales in comparison to the one on the D300 and A700
