You have until December 13 to express your opinion.
It's a lot of technical gobbledy gook, but boils down to the following
Rural Interstates – 75 miles per hour (mph)
Urban Interstates – 65 mph
Rural Multi-Lane Highways – 65 mph, unless an engineering study determines the need for a lower speed limit.
Other Rural Highways – 55 mph, with the option to increase the speed limit to 60 mph on individual highways where an engineering study determines that a higher speed limit is warranted.