Dungeon World represents a very different approach to FRPing than most of the traditional FRPs (Runequest, Thieves World, D&D, BRP, and the list goes on). It differs in that it operates somewhat like a chain story or improvisational theater; You are encouraged to find out things about the world and the characters in play rather than fleshing out a setting ahead of time, the characters seem to have the initiative and a good chunk of the agency in terms of what an adventure will look like and how it will unfold, and the GM is primarily executing the role of the improv partner - when presented with a piece of information, it isn't denied but instead one asks 'and then' or 'yes but' or 'and because of that'.... you work with what the players give you.
Mechanically, they call the actions players take as 'Moves' and the GM responds to moves to add drama, ratchet up the excitement, and to create new things for the players have to handle with their next Move, which again triggers a GM response.
I've not actually played it, because my group can often need prodded to action and a game that requires for them to take narrative control at times and to lead the story is just not something that I feel would succeed. So, a caveat then to my recommendation of this interesting game product: If you have a party that naturally would lean into the role of story drivers, then you have the right group for Dungeon World. If you have a quiet and generally-only-reactive group of players, then perhaps Dungeon World is not for you.
The other caveat I would say is that you do need to have a discussion with your players so that they understand they have a responsibility to make the story interesting but also one not to wreck the story by narrating things that conflict dramatically with previously established campaign facts or setting (too greatly anyway) and they should add interesting things but be aware of the possibility of creating something incoherent if everyone is adding wild, different things that don't work together. It might be better to focus on one character's backstory or his motivations and goals in a scene or adventure more than just everyone throwing in stuff like mad. That would maintain a coherence to narrative that may be more satisfying.
I'd recommend owning this game even if only to see a very different way to run an FRPG session. It's not like any other FRPG I've seen and I suspect it would take some getting used to, especially for experienced DMs and players of other gaming systems that are more 'GM presents the setting and key events, players react'.
[4 of 5 Stars!]