I'm still hanging on above 80 mpg. It was as high as 82.7, but I'm back down to 82.2. I still have two bars left on the gas gauge and am somewhere around 750-775 miles.
Unfortunately the Insight will be parked for a week while I test drive an RX 400h, so I won't finish the tank for approximately another 1.5 weeks.
I'll give an update then.

Eric Powers
Hybridfest Green Drive Expo - A Hybrid Electric Car Show and More! www.hybridfest.com
Third weekend in July, 2009
Madison, WI