I ordered the d90 kit back in October and it came with the Nikon warranty. Just make sure you purchase the body directly from Amazon, not from a unknown company that's selling it on Amazon.com. I use Amazon.com often, but I'm reluctant to purchase merchandise that's not sold directly by Amazon. Hope this helps.
The URL (http://www.nikonusa.com/fileuploads/pdfs/Authorized_Dealers/Nikon_AuthDealers.pdf) does now list Amazon.Com as an authorized Nikon Dealer as of the date on which it was published, December 5, 2008. That doesn't necessarily mean that Amazon wasn't authorized before that, it may have just been an oversight in the Nikon listing.
I just bought the Nikon D90 from Amazon.com and I, too, wondered if it was gray market. I bought it not through another vendor via Amazon, but through Amazon.com LLC. I checked the warranty card AND registered my camera with Nikon and did not seem to have a problem with it. The warranty card says that it is a USA warranty.
Addendum 12/22/08: I just spoke to a NikonUSA rep just minutes ago and asked point blank how can I tell a Nikon product from Amazon carries the NikonUSA warranty. He said that the only way to check ANY Nikon product to see if it is gray market is if it needs service. He also said that Amazon WILL indicate when a Nikon camera is a gray market product. According to the rep, my pricing of $839 for the D90 was consistent with the current product pricing, vs. $572 which was consistent for the gray market product. Hope this helps
If the camera serial number begins with a 3, it is a US version with a US warranty. Here's a list of serial numbers and the countries that they designate. I don't know if this list applies to all Nikon cameras but it does for their DSLRs. Amazon has been an authorized Nikon dealer for at least 2 years. I have bought Nikon gear from them for that long and the registration went through just fine.
Nikon DSLRs Serial numbers beginning with: 2 - Japan 3 - USA 4 - Europe (excluding UK) 5 - Canada 6 - Australia / New Zealand(?) 7 - Asia (excluding Japan) 8 - UK
E: Thanks for the reply. I also wrote Amazon, and they told me: "Many of the items listed on our website are covered by a manufacturer's warranty. This information should be listed in the owner's manual for the product." I explained what gray market meant in my inquiry, but obviously they don't get it at all. The price is so low that I assumed it was gray market.
I agree with you--I would never buy a Nikon product from anyone other than Amazon directly.
This is exactly what I'm trying to figure out. Whether it comes with a warranty card (I assume that's what we're talking about regarding the owners manual) or not seems irrelevent (after all, any hack on ebay can include the warranty card--that doesn't mean Nikon will honor it). What matters (to me, at least) is that Amazon is NOT on Nikon's list of authorized dealers (http://www.nikonusa.com/fileuploads/pdfs/Authorized_Dealers/Nikon_AuthDealers.pdf), and if you're not on there, you're gray market. At least that's what I think . . .
Also, our personal experience has been that less than reputable (read: SCAM) dealers will sell you the gray market camera and then tell you that it doesn't include accessories such as a battery and battery charger, which we all know comes with any legit camera. Best to spend the extra money and buy from an authorized dealer through authorized channels and have some peace of mind so that if it ever needs service, it will be covered under Nikon USA warranty. We bought our D90 direct from Amazon.com (not a seller through Amazon marketplace) and have been very happy with it. I cannot speak for this particular vendor, though.
I recently purchased my D90 (body only) from JR and it has the warranty. If the camera is listed as New it has a one year Nikon warranty. Almost all of the sellers that carry the D90 on Amazon.com have ratings and will tell you if they are reputable. If you are so afraid of buying from Amazon dealers go to Ritz Camera and pay an extra hundred bucks.