Mahjong in Saki
One of the things that strikes me about Saki is how unimportant the actual mahjong games are. While it matters who wins (and sometimes how powerful their win was), the show pays almost no attention to the actual process of playing and winning. This is especially striking in the past two episodes (6 and 7), where the show has been focusing on a tournament.
(Sometimes we get a little bit of dialog about strategy issues.)
This is rather unusual for a nominal sports anime, but does mean that you can follow pretty much all of Saki without knowing more than a tiny bit about mahjong. You won't miss much in being unable to follow the games, because there's usually nothing there to follow in the first place.
(While episode 7 does show some gameplay, my impression is that it is just illustrative; it's there to show Nodoka's dominance, not for anything important about the play itself.)
One reason I like Nodame Cantabile's Chiaki
One of reasons that I like Chiaki is that he is that rarity in anime, a competent protagonist who understands his own competence. The usual pattern is that the protagonist is either unskilled (and learns through the course of the anime) or is basically an idiot savant, ferociously skilled but without understanding.
(Nodame herself is an example of the latter category, and one of the themes throughout Nodame Cantabile is people trying to get her to harness and direct that ferocious skill, to think about and understand what she is doing.)
One particularly blunt way to put the attraction of this is that it means that Chiaki has clues. He comes to realizations; he sees problems; he fixes things. In short, he gets to act intelligently, not blindly. He gets to be smart in his field, which is refreshing to see.
(This is unfortunately kind of a rarity in anime protagonists; being smart this way is usually reserved for the secondary characters.)