Saki definitely got me into mahjong. It also got me into other great mahjong manga/anime, like Akagi and The Legend of Koizumi. However, Saki remains my absolute favourite mahjong series of all, and one of the things I have maintained from early on is that Saki is just as much worth examining from a technical mahjong perspective as more 'gritty' series (like Akagi), even though much of its play is based on superpowers. The interaction between each character's abilities, and especially the strategies various characters must develop and employ to fight against other players' abilities, definitely allows mahjong to bring a whole new level of depth and enjoyment to the Saki series, even if many people have started out simply enjoying it on a character or yuri/subtext level.
Regarding mahjong itself, much of the Saki community on /a/ regularly plays and hangs out at the Tenhou L7447 lobby. In the past there was a mahjong league, and even now they are hosting tournaments. After getting a bit familiar with the basics, I have found osamuko.com and justanotherjapanesemahjongblog (this one is a bit more advanced/technical) extremely good references for improving my mahjong play, and arcturus.su is a great reference for anybody needing help getting around the Tenhou service. Personally, I have been playing with the handle Ako555 in L7447 since about the end of December last year, and also recently started working my way up towards Dan in the ranked lobby (lobby L0), which has definitely been an engaging, sometimes thrilling, sometimes frustrating experience.