Great loose leaf teas, gigantic selection.
They do 'real' tea, have an extremely impressive wide variety, and also sell in bulk at fair prices. 1 ounce of tea for $3-$8 may sound steep until you realize that you'll get 25-30 cups of tea, which makes it even cheaper than mass-prepackaged bags of inferior quality.
Their Japanese teas very closely resemble what we drank in Tokyo and Kyoto, even moreso than the tea we once ordered from the Japanese tea-import website.
Service is the usual run-of-the-mill cafe-quality of hung-over undergrads. The place is also pretty uncomfortable to sit at for doing homework, which is probably partly by intent -- you come here to drink tea, not study for 4 hours.
But overall, you get a quality of product here that's even tough to find in richer cultural destinations like Chicago. I personally come here and buy 2-3 new teas every visit and drink them at my own pace at home. Every tea, green or black, has 'qualities' from relaxation to intensity. And you can really sample a spectrum of tea types here.