Missouri recently got FHWA approval for building some truck-only lanes on Interstate 70. A YouTube video at: http://www.youtube.com/watch?v=VTUf3qZQvf4 explains how these lanes would work.
Personally, I’m very much in favor of dedicated truck lanes. However, I have a concern about the proposed implementation in Missouri. Specifically, ramps going from the truck lanes into the left lane on the mixed-use lanes. I absolutely detest ramps that enter on the left, since it’s extremely difficult to see traffic on the right side of the truck when merging into the left lane. They don’t call the right side of trucks the "blind side" for nothing. According to the video, areas with heavy truck traffic will have dedicated truck on and off ramps, which is good; but I think it would be much safer to have all truck traffic merging in from the right rather than the left.
Of course, making all ramps enter on the right would require bridges or tunnels, increasing the cost of building such a system, but in my opinion would be well worth the money spent for the increase in safety.
The initial 30 mile segment would be built in Saline and Cooper counties, which are about 60 miles east of Kansas City. The plan (if it works out) would be to have dedicated truck lanes from Kansas City to the Ohio/West Virginia line. It’ll be interesting to see how it works.