Thanks Dan

and thank you too Greenunicorn. for this shot I used a Canon FD 75-200mm lens at 150mm and to get the shot I set the F-stop to 5.6, reduced the exposure .7 points (otherwise all you will get is a ball of glow) set the shutter to 1/350 sec. a max aperture of 3, ISO-400 and the metering set to center weighted average.
I am biased towards Canon.. Since that is what I have
I won't lie though I have read a bit about the Nikon D90 and i do think it is a great camera, very comparable to the new Canon Rebel T1i.. But I still lean towards the Canon, like comparing the Nikon d90 to the Canon T1i..
The Nikon books about $1000 (body only) it's shoots up to 12.3 mp. It has 11 points of autofocus, and the iso speed can go up to 6400.
The Canon books for a little under $900 (with 18-55mm lens) shoots up to 15.1. Only has 9 points of autofocus and can only has a max iso speed of 3200.
They both have 3 inch screens but the big difference is that the Canon can shoot full HD (1080p) video, where as the Nikon can only shoot SD (720p) video.
I don't really see why everyone likes the Nikon D90 so much.. but I guess it there prerogative.
Yes.. lenses do matter a lot.. but then again I know very little of the 450D, just that it is more feature rich then the 400D..anyway the basic lens kit is good for every thing from macro shots to basic landscapes ect.. I mean you can most certainly go to a park and toss out some food and be able to snap some decent pictures of animals..
I hear you on that (too cold) When I took this picture it was -5F (-20.5C) so I set everything up inside dashed outside and took a couple shots and ran back in before the camera could freeze up.. the operating temperatures of the cameras don't quite drop that low 
I hope that I haven't rambled your ear off.. Have fun, and I'll take a look at your pictures soon.
Frank.