Boise Weekly says 16 floors, 268,000 square feet.
http://www.boiseweekly.com/CityDesk/arch...crews-begin-work-at-eighth-and-main-hole
Also, if you go to the 8th & Main Facebook profile they have an official rendering of the building completed in downtown. It may not have been revised recently but you get a pretty good idea of how they see it fitting into the skyline.
https://www.facebook.com/#!/pages/8th-and-Main-Boise/264122953606208