According to Thom Hogan Nikon have yet to actually tell anybody about it:
If You're in the Market for a D5000
July 27 (news, opinion)--I mentioned that Nikon hasn't officially notified dealers about the problem in my original article below. I've now had the chance to talk to a couple of dealers this morning. Yes, there's still no official notification from NikonUSA as I write this (there's a dealer Web site, amongst other methods of communication, but nothing specific on that Web site, and no email notifications yet, either).
However, dealers that were concerned about their current inventory apparently are being proactive. NikonUSA is issuing return authorizations for a dealer's existing D5000 inventory as long as it is matched with a new PO to replace the impacted cameras. The replacement cameras should be into dealers sometime next week.
Thus, if you're in the market for a D5000 at the moment, talk to your dealer about whether their inventory has been checked for cameras affected by the Service Advisory. This is one place where having a good local dealer makes a difference. The good ones are on top of this and are already replacing their inventory.
