The April 2007 issue of Exclaim is running an article called "Next Episode" on the recent spate of 'episodic' game releases (Sam & Max, Half Life 2, et. al.). In an odd reverse, the article remembers to credit Secret Ops... but associates it with an odd conclusion:
Pioneering episodic games Wing Commander: Secret Ops (1998) and Majestic (2001) were both cancelled before completion; the former was too large a download in the pre-broadband era, while the latter simply failed to attract enough players.
So, before anyone asks -- no, Secret Ops wasn't "cancelled"... all seven episodes were released as planned, and no others were ever considered.