The second one is only releasing in the west next week for PSP, but Sega’s ramping up for Valkyria Chronicles III, by the looks of it.
The publisher has registered the URL “valkyria3.jp”, which seems to suggest a third game in the series is coming.
As Andriasang points out, this could be Sega protecting its interests and just safeguarding the URL before someone else gets it.
We do hope it is a sequel, though. Hopefully on PS3 again. TGS reveal, please?
Valkyria Chronicles II releases on PSP next Tuesday in the US, with a EU launch next Friday.