Near instant worldwide transfer of funds with low fees is a big one that comes to mind. I'm invested in bitcoin and it takes, on average, an hour to move around with around $10 in fees.

Of course the fees are still high but I imagine they will come down if bitcoin wants to see mass adoption.

Immutable, anonymous, and decentralized ledger.

Those are attributes of blockchain technology rather than bitcoin itself though. It's possible another cryptocurrency (litecoin anyone?) will dethrone bitcoin as the 'currency' and bitcoin will remain a store of value.