Savage B.Mag comes out this year. Its the new .17 WSM, a brand new rimfire that drives a 20 grain 17 caliber bullet at 3000fps. MSRP:$350
I think it would knock a coyote as dead as a doornail. I think it would be perfect for coyote, an entrance wound so small it will be hard to find, unlikely for there to be an exit wound so if you want the pelt it will be very intact.
My advice is to find a gun you are comfortable with. An AR-15 might be a good option if you want to try and hit more than one before they scatter and be able to keep shooting as they scatter. If your fine just going out and shooting one and maybe two, a bolt action will do the job just fine. The ideal coyote gun should be light enough to carry comfortably.