I've been enjoying Rusty Hearts greatly since it launched as an open beta. It's a bit repetitive, but I have been finding it to be lots of fun regardless. My biggest concern was the lack of content at launch, and the frequency at which new content would roll out. Thankfully, the future of the game seems good, with a second content update this month. It doesn't bring anything new in terms of dungeons, but instead adds a new character to the fold.
Natasha has actually been known about since the closed beta, and fans have been wondering about her for a while. Originally scheduled to launch on Wednesday, she officially is playable as of today. She offers a new play style, which the developers have graciously decided to detail in a video. In addition to this, Rusty Hearts now has integrated Steam Achievements.
You can read more about Natasha here, as well as register a Perfect World account if you want to check out the game.