Syncaine has another interesting Darkfall post up on his blog discussing why he thinks some players have started experiencing burnout so soon after release. He feels some of the issues are a result of how the game world has been playing out, while others are attributed to individual play style.
Game specific issues include large alliances that have been forming up in Agon and that some people feel they must keep up with the Joneses. Being in an über-alliance means that nearly (if not) all your neighbours are friendly and that you must travel far and wide to find any PvP. Perhaps due to exploitation methods in the past (e.g., being able to skill up on invincible mobs), some players feel they need to grind before they can be truly effective in the game.
Play style specific issues include trying to play a sandbox game with an "on rails" mentality and that some people simply can't handle the notion that for every triumphant gaming session, they will probably encounter an equally disastrous one. While some people think they crave a wide open, hardcore PvP experience, they refuse to accept that it may not actually be their style.