A game only for true lovers.
HM:DS is based on FoMT in the town from AWL. It's supposed to take place 100 years in the future. (If you connect to mineral town, then go look at the big rock above where the construction site is, it will say "Here lays legendary farmer "_____" from your mineral town.) There are 9 Bachlorettes (Muffy, Lumina, Celia, Naomi, Flora, Harvest Goddess, Witch Princess, and two new additions to the series; Leia the Mermaid and Keira the Cave Princess... or something.) You can also married the girls from Mineral Town, but in doing so you end your game.
The Witch Princess has a prank go wrong, and all the sprites and the Harvest Goddess Disappear. Obviously, you are called to find the 101 sprites, and free the Harvest Goddess. (This becomes a pain when you have to find 60 to get married.) You find them by doing things such as shipping 1,000 items and breaking 100 stones, just general things you would do playing the game like you're supposed to. They also have something called "Sprite Stations." There are nine sprites (named after the planets) that host television shows accessable from your rucksack, which takes up the bottom of the screen. One is the television show, one is the weather, etc. You have to find them also by doing random things around your farm.
Some new features have been added, such as the fact that your farm comes with nothing, and you have to work to buy it all from Gotz. (The stores are called from your house, instead of going through the town.) You have the choices of building your buildings out of fodder, wood, stone, or golden lumber. Fodder is obviously not the sturdiest thing in the world, and golden lumber is unbreakable. Buildings fall down. If you have cows in a barn made of fodder, and it's raining, it's possible that your building will fall and all your animals will die.
Other features have been added like there are for different mines, with the levels going from 10 in the first and 65,335 in the last. (How you're ever supposed to get through that many levels... Don't ask me.)
A few other things have been added, that make the game a great addition to the Harvest Moon series.
On the bad side... There are many, many glitches. None of them seriously mess up your game, but some of them are worse than others.
In conclusion, I really love this game and I think if you truly loved FoMT or MFoNT, you would love this game and it's worth the money.