Before there was the Lorebook in Lord of the Rings Online, there were titles in Guild Wars. Before there was the Tome of Knowledge in Warhammer Online, there were titles in Guild Wars. Before there were Achievements in World of Warcraft, there were titles in Guild Wars. This title system has been in place for a few years now, and has been steadily growing to incorporate achievement recognition for many of the game's favorite activities. In yesterday's game update though, the entire title system got a revamp.
One of the biggest problems many players saw with some of the more difficult titles is it felt like pure grind. To remedy that, ArenaNet has adjusted the difficulty of a few higher-end titles, and changed the way titles affected things like Favor of the Gods, Vanquishing bonuses, etc. Check out the complete patch notes at the developer wiki page for more information.