The upcoming anime fall season, Log Horizon 2 get promotional video with duration 23 seconds. The PV that uploaded on the NHK website, reveal some scene on the second season.
The opening theme from the first season "Database” by MAN WITH A MISSION and the ending theme "Your song*" by Yun*chi will come back in second season.
Log Horizon second season will be released on October 4 in Japan by NHK's E-Tele channel and scheduled to air for 25 episodes.
Source: ANN, JOI