Natsume has confirmed that Harvest Moon: The Tale of Two Towns is headed for a simultaneous DS and 3DS release in US this summer.
Tale of Two Towns is the latest game in long-running farming sim, having released in Japan on DS in July last year. This one tells the story of two once friendly towns who are now locked in a feud over which town has better food.

Natsume CEO Hiro Maekawa promises a "great new cast of characters, fun festivals, and exciting new gameplay mechanics".
It's unclear what changes/enhancements will be made to the 3DS version other than the obvious addition of 3D effects.
Here's a Japanese trailer for the DS version from last year.
Comments
2 comments so far...
nick_gc on 8 Apr '11 said:
I used to love Harvest Moon games. The recent releases, to me, have just felt a little unpolished. Which kind of furstrated me into not playing them any more.
TimHotston on 8 Apr '11 said:
If you want an alternative to Harvest Moon check out Rune Factory, it is basically the same except you have weapons and have to defend your crops from monsters/orcs.