what camera system to use for telephoto work?

Hi, Im a keen amateur wildlife photographer, but I keep doubting what gear I should be using to get the best quality and detail. To cut a long story short I've in the past started with nikon, switched to canon then switched back to nikon ( don't ask why it was before I was into wildlife photography though I'd snap some swans and ducks back then). Currently Im using a Nikon D90 and Sigma 150-500mm OS but Im not sure if Nikons range of telephoto lenses especially once I start going high end and the camera's they have are as good as Canons. I know fieldcraft and technique all play a part as well as PP on your pics but I keep looking at people's pics from Canon gear and Im always blown away. I know it's high end stuff but when searching for shots taken with High end nikon gear I come up short and when I find it there's never the Detail there like the canon shots. Is this just me or is this because Canon seems the preferred choice amongst most wildlife photographers?

In my own opinion Im still totally blown away by the 5D mk2 aswell as shots I see from the 1D mk3, but Nothing from Nikon seems to have that biting sharpness like these 2 except maybe the D3x...

As you can see it's starting to bug me so an unbiased opinion would be really great!

IMO the lenses are going to be a lot more important in factoring this decision. realistically D300 = 7D, D700 = 5D2 (with each having it's strengths) and 1D3 = D3, 1Ds3 = D3x.

If you can really afford long lenses of 500mm or more then IMO there is not much between the companies.

If you want to work with zooms, then the direct comparison has to be cheap & slow (Canon 100-400L) vs. expensive and fast (Nikon 200-400/4 VR).

Well the first thing that comes to mind is the new 7D. It's gotten great reviews as far as high ISO shots up to 6400. It makes your lens a little longer for reach. Your right about the 5D Mark II but your 400mm lens is 400mm. With the 7D it acts as 640mm. Excellent for wildlife photography. The Mark III has about the best IQ I've shot, but its only 10 megapixel. The 5D Mark II has 21 megapixel and the 7D has 18 megapixel. If I were shooting wildlife and landscapes the 7D would be the camera I would be using out of the 3.

JeffreyG wrote in post #8786414
IMO the lenses are going to be a lot more important in factoring this decision. realistically D300 = 7D, D700 = 5D2 (with each having it's strengths) and 1D3 = D3, 1Ds3 = D3x.

If you can really afford long lenses of 500mm or more then IMO there is not much between the companies.

If you want to work with zooms, then the direct comparison has to be cheap & slow (Canon 100-400L) vs. expensive and fast (Nikon 200-400/4 VR).

Just FYI, while the Canon 500 f/4 IS is goning for around $6400, the equivalent Nikkor lens is over $8k..!!!

DennisW1 wrote in post #8786538
Just FYI, while the Canon 500 f/4 IS is goning for around $6400, the equivalent Nikkor lens is over $8k..!!!

If you have to ask what it costs, you can't afford it.

You did just remind me though, Nikon has no 800mm or 1200mm prime lenses to compete with Canon.

Thanks for the help so far, I should of said Im pretty much a gear head more than anything actually. Im aware of the crop factors and prices and I'm always looking through the lens sample archives and flickr ect. Oddly the Nikon and Canon 500mm F/4 here in the UK is almost the same price with Nikon actually being cheaper on supertele's in some cases.

Is the 7D really that good for low noise as from what I've seen although it does look fine at 6400, lower ISO around 400 looks more noisey than my D90. Im sure thats down to it being 18Mpx compared to my 12Mpx at 100% and crammed into the APS-C sensor. I don't think I would go for the 7D however for pretty much that reason just too many mpx in a smaller sensor. The 5D mk2 although not a Wildlife camera at heart seems to have biting sharpness and thats kinda what Im after.

I guess lenses are the key here really and again I feel sort of limited by nikons current range, Although the Nikon 300mm F4 is good it is about the same price as canons and lacks any VR/IS. Nikons 80-400mm VR is from what I've read pretty rubbish with very slow AF and first gen VR, compared to canons 100-400mm L IS which I see some stunning shots from. Canon also has the 400mm L F5.6 which although has no IS I see some amazing shots from, and nikon has no comparison for.

Im really unsure what to do once I have the funds to upgrade from the Sigma lens as it's a great lens even at 500mm but lacks in a few area's for me.