Congratulations to all of us!
A lot of fun through these 5 years, but 3 most memorable moments in SWTOR happened to me pretty early in the game:
1. Finally getting to play first time in beta and first time at launch (those server waitlists were killing me!)
2. Connections to KOTOR: walking through the doors of Endar Spire on Taris and hearing the KOTOR theme, and, especially, meeting Revan first time in the game in Maelstrom Prison.
3. Finale of Inquisitor's class story, that cutscene right after the final fight is epic.
In general, SWTOR Story is awesome all the way, along with brilliant voiceacting (or just decent for some classes), and beautiful soundtrack.
As for main activity, I spent a scary huge amounts of time in PvP, so exciting at first, and addictive later.
Thanks for letting us enjoy a part of our lives in a beautiful Star Wars universe!