Classical Fighting Arts (published by Dragon Times), is excellent! It is composed of hirstorical and technical articles on Japanese, Chinese, and Okinawan arts, with a focus on Okinawan Karate. Another great one is The Journal of Aisian Fighting Arts. The articles are interesting and long, focusing again on the east asian arts, and mostly composed of historical and theoretical research articles. Eleven of the editors for the Journal are Ph.Ds, so there you go! Both are published four times a year(or maybe six?), are available at SOME Barnes $ Noble bookstores, although are hard to find, and are available for subscription, of course.
Definitely a big step up( for the classical warrior), from Black Belt Mag!
By the way: who saw the latest issue of Black Belt with the cover article featuring XMA? Pathetic; and they're doing a part two of the article next month!