Canon Digital Rebel XTi | Reveiws | Technical Info. | Videos
The next best specific to the Canon brand only? That’d be the 30D, mostly because it’s built to more rugged specs and is a faster performer all around. Ergonomically it’s designed much better than the XTi, easily able to accommodate larger hands.
The XTi has 2mp more than the 30D but at that difference, not a single person would notice the discrepancy, so in my personal opinion, the megapixel factor is moot.
If you want to know what’s better than an XTi compared to other brands, then I couldn’t answer objectively. Look at it this way, there are many, many better models out there simply because they’re designed for professional-level use and abuse, and/or they produce far superior images. Within approximately the same price-point though, you basically have Nikon D80, D40x, Pentax K10, K100, Olympus e410/e510, Sony A100…
Now, *personally* my first choice among all the above would be either the Pentax K10 or Oly e510, while my last choice would be the XTi, closely followed by the Sony A100… I have my reasons but the gist of it is that everyone will give you a different answer, and their preferences will be 99.99% subjective. And hey, I own Nikons, which at the upper level of models I do prefer.
Bottom line? If you’re itching for a dSLR and the XTi looks pretty good to you, go out and pick one up. It won’t disappoint you as long as you don’t split hairs in comparing it against other models. It’s the photos that count in the end, and the XTi will not disappoint in the least in that department 
References :
Nikon D200
Check the specs on the link below. They look pretty similar don’t they.
Well not really. The D200 is based upon a true professional SLR camera and has three features a pro needs to make their lives a little easier.
Image comment. Your copyright notice can be embedded on every image you make with the camera.
Image authentication. It proves that the image has not been altered. This is important under at least three conditions. 1) when the images is going to be used in a court of law. 2) if your images is ever stolen and there has to be proof that the file you have is the original and 3) if you are an editorial or photojournalist and someone claims that your image has been altered. IA will prove that YOU did not alter it.
And finally the electronic flash Commander mode. This feature allows the photographer to control remote flash units using a radio control from the camera, plus other additional options.
There are also optional things like the MB-200 which will hold two batteries, a WiFi attachment and GPS recording mode.
References :
http://www.dpreview.com/reviews/compare_post.asp?method=sidebyside&cameras=nikon_d200%2Ccanon_eos400d&show=all
Editorial, sports and glamour photographers
Hmm lets start from the closest…
30D for speed, 5D for imagine quailty, MK-III for imagine quailty and speed, Hasselbad for that 32MP…. lol jking
For serious uses the 30D or the D80 would be the next level up. I would personally take the 30D over the D80 though.
References :
Again, why do you want to invest in Canon Rebels when they do not address the issue of "image stabilization/vibration reduction." Do you want to carry around a tripod for those telephoto shots? Instead, look into the award winning Pentax KD DSLRs which incorporate image stabilization into their camera bodies. You may be wasting your money in going with the Rebels without "image stabilization." And have you checked out the Canon EOS series of specialized "image stabilization" lenses and how expensive these lense are?
Good luck!
References :
If you are not hung up on the Canon brand name I would say the Nikon D40 or D2x is above that Canon.
References :