Earlier this year US Airways cut their routes to Las Vegas from Calgary and Edmonton as part of a larger program in flight reductions out of LAS.
It appears though that the Edmonton – Las Vegas route has been reinstated and will be starting on Sep 11 (the incoming flight will leave LAS on the 10th) . It looks to be a 4x weekly routing for September (Mo,Tu,Fr,Sa) and then goes daily in October. The direct link will then end on Dec 16. Flights are operated by regional carrier Mesa Airlines with a CRJ900 as follows:
YEG-LAS Dep 630 Arr 832 x
LAS-YEG Dep 2128 Arr 139+1