Nico Nico is now listing three winter series: Senki Zessho Symphogear, Detective Opera Milky Holmes 2, and High School DxD on the anime portion of their website. All three shows are listed as being available as in US and Canada only and do not have dates or times that the episodes will be available as of yet. More details about each show are available on the respective channels on the website.
Update: Nico Nico announced dates and times for the new series to kick off:
High School DxD
Senki Zesho Symphogear
Detective Opera Milky Homes 2
FUNimation has licensed High School DxD for home video and will also be streaming the series beginning today.
Image ©Project Symphogear