This is a great magazine for fans of jazz and musicians alike. Each issue has ~200 pages with a full-length sampler CD included. There are interviews with contemporary artists, features on jazz legends, and ~100 CD reviews every issue. Also, the magazine includes transcriptions of classic jazz tunes and solos from artists such as Wes Montgomery, Pat Martino, Miles Davis, John Coltrane, etc. There are several lessons in each issue, although they tend to be geared more towards intermediate to advanced players. Don't let that scare you away if you're a jazz novice like me. With enough patience, I have worked through several of the lessons which I initially thought were over my head.
The magazine is for musicians of all instruments, not just guitar. Mostly standard notation, although I have seen some tab when the transcriptions are specifically guitar-oriented. Also, the editorial content tends to be biased towards classic jazz- not much in the way of fusion in here.
That being said, this is a great resource. It is relatively inexpensive (~$40/4 quarterly issues with CD included), and thoroughly informative.