I have been listening again to the two guitar duet albums that Bireli Lagrene and Sylvain Luc recorded (Duet and Summertime). Probably the best acoustic guitar duet recordings I am a aware of.
Also, there is a “new” Pat Martino album. Actually, it is a live recording done more than ten years ago but just recently released. It is another duet record but this time it is guitar and piano (with Jim Ridl). The album is called Nexus and it has some really nice moments.