Someone already posted re-seller ratings... but really... it needs to be said that if a deal on camera equipment looks too good to be true (especially when it comes to newer models) it probably is. Camera equipment holds it's value pretty well and any 'discount' you get at these other shops is usually a scam.
The most common is to 'sell' you the camera over the internet. Then a couple of days later you get a phone call from a high-pressure sales person saying "Well, you'll need a battery charger. And a camera manual. And a lens. And a filter. And..." You get the hint. A lot of the stuff they say you 'need' - like the charger or manual - are already included if it's from an actual Nikon/Canon dealer. These little 'extras' end up costing you more than if you had just purchased from a reputable dealer and if you don't bite on their scam, then they 'cancel' your entire order.
Additionally, a lot of these cameras are referbs or imports. While there isn't anything necessarily wrong with an import, you need to know that you are buying one, because the warranties aren't always valid.