Mythos will cease to exist in the EU on October 27, 2011. Frogster made the announcement via the official Mythos forums.
According to the post, the game launched successfully with a lot of users taking part. However, the "long term success did not materialize" as developers hoped it would.
For the next several days, players can request and receive any missing quest items to ensure that all incomplete quests are finished prior to the game shutdown. In game purchases through the item store will be discontinued. XP and buff bonuses will be in place for the duration of the game's life.
To thank the community for its support of the game, Frogster will be handing out Runes of Magic vouchers that players can use to purchase diamonds, mounts or both.
Read the full post on the Mythos forum.
Thanks to Piasek for the tip!