It adds new missions, weapons and gear, new customisation and a revamp of classes and skills - all free to subscribers. Its add-on goes free also.
The Ambition of the Illuminus expansion was 800 MSP but the 'Guardians Advanced Content' update lets you get it for nothing now. Phantasy Star Universe is the sequel to Dreamcast's Phantasy Star Online, and this new MMO launched back in '06.
Are you a fan of Phantasy Star Universe for Xbox 360? It's also for PC.