According to an official announcement, the upcoming material John Frusciante will release is an EP, entitled Outsides. It will be out on August 14 in Japan and August 27 in the rest of the world.
Outsides will consist of a 10 minute guitar solo and two "out" pieces of music (hinted as free jazz by Frusciante himself). The bonus track 'Sol' is available as an instant download after pre-ordering the EP.
The EP cover and a lengthy description of the music on it can be accessed on Frusciante's official website - http://johnfrusciante.com/