Probably been asked a million times, but I just started reading this thread and I'm 2 pages in (100 posts per page)
Q: I beat "The Truth" and the mission where Quiet leaves. Was that the end? Been doing side ops and Mother Base stuff, but there hasn't been any more progress. Sounds like the closest thing to an ending is the cut stuff? 55% overall completeness, 49/157 side ops, 6 more of the 50 main missions (5 extremes and 1 total stealth) I need to get back to normal life, and not play these ridiculously hard repeat missions. I heard there was a Ture ending for beating all the missions, but enough is enough.
EDIT: I've also listened to all the tapes so far... I guess this is the bulk of the story.
I was disappointed at the end of the first half of the game, I kept saying there's no way this could be the ending. But then I remembered every mission was like the end of a TV show. I actually feel worse about the game/story after the 2nd half. While I guess I'm somewhat concluded about the events of this game, the pacing was pretty bad, and nothing of what I thought would be answered about the MGS story has been in this game.