Saki originally attracted me through its moe schoolgirl designs, as I've not the slightest idea how to play Mahjong (and I have to admit I have only slightly more of an idea now than I did before watching it). The mahjong scenes, interestingly enough, turned out to be some of the most riveting variations on 'battle' scenes I've seen in awhile. If lightning blasts and magical girls really popped put when people slapped down the tiles, I'm sure this game would be much more popular in the US.
In its two cours Saki develops a huge cast of girls, both Saki's teammates and their rival schools. I kept waiting for Saki and Nodoka to make their obvious yuri love official, but other than some suggestive scenes of sleeping together there's never even a kiss. There's a LOT of implied yuri in this series, but again, nothing beyond excessive blushing at one another and sparkles. Well, and Saki ogling her girlfriend's huge boobs, but so does everyone else in the series. There are virtually no male characters to speak of, and those that exist are mostly ignored since every one of the girls is a raging lesbian. Mahjong makes little girls gay, I guess?
The massive cast is as much a weakness as it is a strength, as you almost can't help but pity all these girls who have motivations for winning but are going to get steamrolled anyway by the monster that is Saki. Seriously, as OP as Ichigo is in most of Bleach, Saki is in her own show. There are some tense moments where the show almost convinces you she could lose, but a glance at the episode count and/or title will remind you of who the mistress is.
Story 6/10 (largely revolves around two tournaments, a brief training arc, and yuri)
Art 9/10 (who knew mahjong could be so badass?)
Sound 8/10 (nice and dramatic soundtrack, stellar cast)
Character 7/10 (some are a bit shallow but you could fall in love with almost any of them)
Enjoyment 8/10 (I followed this when it originally came out, and it kept me riveted from episode to episode)