Maxell has announced that they will be releasing their new 25GB BD-R and BD-RE media to the Japanese market on December 8th. Here's part of their press release, translated from Japanese:

It is BD-R/BD-RE disk (one one side layer 25GB) for recording that Maxell puts on the market this time where it answers needs of the high-definition television recording to such removable mass storage. A large capacity and a steady record and the reproduction characteristic are achieved by inorganic/use of the achievement of BD Stampa and the high recording density that processes the narrowness track pitch ditch shape for a blue purple laser precisely and smoothly of the aspect change recording layer and 0.1mm cover layer making technology, etc.The digital Hi-Vision broadcasting can be recorded for 130 minutes like the high-definition television image quality corresponding to five mass times or more record the memory capacity 25GB(one one side layer) and DVD. Moreover, this product adopted the hard court where the record side was defended from Kiz by the type of the cartridge none to which the disk record side was exposed.
According to AV Watch, Maxell's BD-R and BD-RE media is expected to cost about 1,800 Yen and 2,500 Yen respectively. More information can be found here.