The road upto the Nagarhole Park entrance is done, but beyond that has been stopped because of environmental objections (rightly so), last heard that road is practically non-existent after the check post beyond the Karapura turn-off. Better option if you would not mind the bad sections near Kutta is to take the Srirangapatna - Hunsur - Murkal - Nagarhole - Kutta - Tholpetty - Mananthavady route. The best option has to be Mysore - Gundlupet - Bathery - Mananthavady.
This post gives the latest update
http://www.team-bhp.com/forum/travel...ml#post1013820 (Bangalore-Mysore-Hunsur-Gonikoppal-Nagarhole-Kannur)
Cheers
Srikanth