Canon has launched the 500D/T1i, this fits in between the entry level 1000D and the professional series 50D. This also have video capabilities which all the SLRs are now adding.
- 15 Mega Pixel. Same sensor as the 50D, which is a good thing but does megapixel matter any more? Perhaps for some.
- High Definition Video (1080p) recording.This is at 20fps, while you can get 30fps if you shoot in 720p.
- Extendible ISO up to 12800
- Live view with Face Detection
- HDMI output
- 9 Point autofocus
- SD/SDHC Card
- 524g weight
Main advantage over 450D
- Video capabilities
- 15MP vs. 12
- Higher ISO vs 1600
- HDMI connectivity
If these are not important to you, then you could get a 450D at a bargain.
Advantage over Olympus E620
- Video as the 620 doesn’t have video.
Advantage of Olympus E620 over Canon 500D
- Image stabilisation in the Body