Technical specs are good for narrowing down your short list of cameras, but the final camera choice you make should be based on personal experience. How does the camera feel in your hands, is more important than burst mode, ISO quality or the size of the image sensor.
The Canon only has a 1.8-inch LCD screen while the Olympus has a 2.5-inch LCD screen. The Olympus has a image stabilizer while the Canon has a multi lens capability. For the money, one would buy the Olympus over the Canon although they are the same price.This helpful tips on how to use a digital camera and this canon eos 40d should help.
A word of warning when using megapixels to compare digital cameras. Be sure to check for image sensor (CCD) quality and size as well.
There’s of course no rush, taking your time is never a bad decision with complex purchase. You may be tempted, to wait a little longer, and see what the manufacturers offer next week, next month, or next year. While I’m sure, it will be something better, be warned that this cycle never ends. There’s always something better coming out tomorrow. There will come a point when you need to make a decision, and start taking pictures.
Don’t get overly hung up on technical specifications for each camera. A few extra megapixels here and there aren’t going to make much difference. For a first time SLR buyer, as long as you get a good lens, with at least 8 or 10 megapixels, and a solidly constructed camera body, you’ll be content.
What I’m trying to say here, is that just about any SLR camera you end up buying will be a good one. That’s not to say, that there aren’t some lemons. If you stick with one of the major established brands, like Canon, Nikon, or Olympus your pretty much guaranteed to make a good choice. The Nikon D60, the Canon Rebel line (XT, XTi, XSi, T1i), or an Olympus Evolt E510 are all excellent choices. Considering you’ll pay the same or less for one of those, that you would have paid for a basic point-and-shoot camera five years ago, is a testament to how far digital cameras have evolved.