Hopefully there will be more variation in the Katanas this time. Like a daedric katana for instance...
There was a Daedric Katana in Oblivion. Goldbrand.
However, maybe we get different kinds of katanas this time (ebony akaviri katana, silver akaviri katana, etc.. deadric wouldnt make sense though, since the blades forged them. )
There was also a Ebony Katana in Oblivion, it was the "Ebony Blade". In the previous TES games (Daggerfall, Morrowind) there were Daedric Katanas and Daedric Dai-Katanas. They were the best 1H and 2H weps in both games.