In a nutshell, Ryuutama is a Japanese game about traveling that uses old school-ish mechanics. You play common folk (a Farmer, a Herbalist, a Hunter, etc) who at a point in their life feels the necessity to undertake a journey to see the wonders of the world, so its focus is more what you do to survive along the way than fighting monsters (for what I've heard, the combat system is pretty lethal).
Probably the most interesting and unique aspect is that the GM has his own character with its own special rules. The Ryuujin (Dragon) the GM chooses to play changes the focus of the campaign and how certain rules work (for example, a Black Dragon is about tragedy and betrayal, while a Red Dragon is all about exploring dungeons and fighting monsters). The Ryuujin follows the group from afar, recording their adventures, and may even be able to help the characters from time to time.
Now, there are many elements of the whole endeavour that I find bothersome (the saccharine cutesy pseudo-European Japanese art; the fact that some RPG nerds are doing the translation and I have been doing translation professionally for a long time and I am an awful snob about it; the fact that a lot of it seems aimed at 11-year-olds; the fact that the combat system is based on the Final Fantasy one) but at its core, this seems to be a game focusing on wilderness travel and adventure with interesting twists, which is something I have been wanting, or wanting to make, for a long time. And who am I kidding? I might be a grumpy old skeptic but I may as well own up to thinking that Miyazaki Hayao's Oregon Trail sounds actually rather nice. (And I am fairly sure the rules can be used for scenarios that are altogether different...like Lewis and Clark in Pandemonium or The Rough Guide to the Elemental Plane of Ooze or Let's Explore the Leviathan's Intestinal Tract or A Beginner's Guide to Caving in the Underdark or The Dream-Quest of Unknown Kadath, pt. II.)
However, a genuine problem, I have to confess, is that I think I am just getting too old for learning new systems. I don't have the time, energy, or willpower to even read RPG rulebooks nowadays, let alone actually take the time to learn the system properly. I have about a dozen rulebooks on my bookshelf of which I've read about one page each, because even flicking through them I begin to feel the onset of brain stem death. Which says nothing about the quality of the writing or the way the rules are presented, and everything about the fact that I've reached a stage in my life where I simply can't summon up the effort or concentration to bother figuring out the way a new system works.
It says a lot about Ryuutama that it can seem both incredibly annoying and intrinsically tiresome because it's a new system and I'm lazy, and yet at the same time manage to appeal to me quite strongly. That in itself seems to warrant a purchase, don't you think?