An anonymous coward spotted this article on episodic games over at Wired. They mention Secret Ops, but get a few things wrong:
[...]it will have succeeded where other episodic titles, like Electronic Arts’ Majestic, and Origin’s Wing Commander: Secret Ops, have failed. Both games were discontinued after neither attracted significant numbers of players. Mainstream gamers bristled at both the pacing and the intrusive quality of online conspiracy game Majestic, while the large download size of each episode of Wing Commander: Secret Ops (about 120 MB) prevented the game from catching on at a time when most people used 56K modems to connect to the Internet (the game was released in 1998).
Secret Ops added up 120MB with optional speech pack, but a slimmer 60MB version was available for download in 20MB segments. The full version also appeared on many cover discs, and the episodes themselves were hardly over a megabyte. Secret Ops was not discontinued: all episodes were released and the game was later bundled with Prophecy in a package called Prophecy Gold.