As of December 12, 2012 the game changed its business model: similar to Guild Wars, after buying the game once there are no monthly payments required anymore. However, an optionally subscription offers advantages like monthly points which can be redeemed in the store, e.g. for DLCs (so-called "issues" which continue the story and add other content). The first four updates are free for every buyer and update five is free for everyone registered in 2012.
GameStar (Germany) / GamePro (Germany)
2012 - #5 Best Online Game of the Year (Readers' Vote)