Hmm.. For a newbie, concern is Mpixels rite? 400D got more mp, so get that!
But really, for me, I took the 400D, not because of mp, but because I'm more comfortable with Canon. If you have a canon PnS, and find that it is good, reliable, den get the 400d. If you think Canon not reliable, dont get it. g luck.
Oh ya, as for lens prices, you can look at the forum price lists to compare the prices of the "same" lenses fromt he diff brands.
Yesterday I was reading on the spec of the canon 16-35L f2.8 II. The review gave it 5/5 rating. You can consider getting canon as I personally feel that their lens are better. A bit regret getting nikon.
Just remember that, which ever company you chose (Nikon or Canon)..... once you start buying a few more lens or parts, you are very much 'struck' with that company for good...... Goodluck on your choice.....
i feel that the D40 is designed in such a way that its a simple to use camera, so if u dont have alot of interest in getting into more serious photography it'll be bloody good, while the another hand canon 400D is more like an entry level that allows u to get into the SLR world (the availability of lotsa lenses). However both are very nice choices, two highly competent companies and i'd say try them both, buy one that you like. Don't look at megapixels too much, its the lens and other factors that matter. No matter how good, if the camera doesnt feel good in ur hands you'll always be limited by that... hope that helps
In terms of function, 400D don't have Spot Metering, which is quite important for portrait shoot.
Fully agreed that your are actually choosing a camera system, in which you are building up for the time to come. For me, I started off with D40 & is very comfortable with the Nikon's build & quality, both in camera body & lenses. Now I have upgraded to D80 & keeping some of the beloved lens.