LucasArts had better
make a sequel in some form.
Sev's disappearance was too abrupt; no one knows what happened and Delta squad inevitably wants to investigate. Besides, what they were called away to do at the end didn't sound like something that would take forever (or maybe I'm not remembering correctly. )
In any case, the way LucasArts left us hanging at the end makes me
hope they're planning on wrapping the story up.