TV Guide reports:
The new Stargate's universe is expanding. On the heels of the announcement that Trainspotting's Robert Carlye will front the new Sci Fi Channel series (playing Dr. Nicholas Rush), TVGuide.com has learned exclusively that Justin Louis and Jamil Walker Smith have joined the nascent cast.
Louis (Hidden Hills) will play Colonel Everett Young, an experienced and married Stargate team leader, while Smith (Hey, Arnold!) will portray Sr. Sgt. Ronald Greer, a Marine with an explosive temper...and a mysterious past to account for it.
Justin Louis has a pretty extensive resume at http://www.imdb.com/name/nm0521878/
Jamil Walker Smith's resume is at http://www.imdb.com/name/nm0808607/