H.B. 124 was signed by Governor Dave Freudenthal on February 28th 2007. It went into effect on July 1st 2007.

AN ACT relating to eminent domain; establishing reclamation
and restoration requirements; defining public purpose;
requiring notice; requiring surveys to be provided to
condemnee; providing measurements for good faith
negotiations; providing for mediation or arbitration;
providing for determinations for fair market value;
providing a presumption; limiting condemnation authority in
urban renewal; eliminating the maximum amount on relocation
expenses; and providing for an effective date.

You can read the full bill here:
http://legisweb.state.wy.us/2007/Bills/HB0124.pdf