Everything is against Xbox One version. Lower install base, less popularity among that platform and non existent presence in Japan (Souls games sell well in Japan). PS4 version will have most of the sales.

PlayStation have more Souls games fans than Xbox due the Demon's Souls.

So no.

And I see gamers buying PS4 for Bloodborne that will help more sales to Dark Souls 2.

Sure life time PS4 will have the upper hand, will be interesting to see the initial opennings though

Playstation pretty much elevated this genre and made it its own. This will still sell better on PS4, especially when you add in Japan.

I understand what the OP is saying. But I don't think everyone who likes Demon's Souls is gonna pick up Bloodborne before it. Now, I know quite a few people who intend to get both. But, those whom I know will skip one day that it'll be Demon's Souls they pick up first because they're already familiar with the franchise.

Probably not. Souls fans seem the type to buy both

No. Just like almost every multiplat game, it will sell better on the PS4.

DS2 remake sales on PS4 might suffer a bit due to the close Bloodborne release, but I think it won't be enough to make the X1 version pull ahead

Absolutely no chance!
I think 360 has really warped people's perception of what the actual XBOX playerbase is like.
360 stole a lot of PS2 players who had some interest in trying different games, but those people are mostly back on PS4 now. And the hardcore XBOX fans are the type who will buy every Halo, Gears, CoD, Madden, and barely touch anything else.

What about PC?