The Nikon D5200 is rumored to be announced next week – on November 6th, 2012 (±1 day based on your location). The new DSLR camera will be on display during the Salon de la Photo show in Paris (November 8-12, 2012).
Nikon (and many other companies) still like to introduce new products before a major photography show – this was the case with Photokina, PDN Photo Plus and now with Salon de la Photo. The next two major shows are CES in Las Vegas (January 2013) and CP+ in Japan (February 2013) and I am almost certain that Nikon will announce new products in the January/February 2013 time frame.