What will be the single player be like.. what type.. very exiting..

I hope for a "goldeneye" type of game.. mayby with a litle more "party" in some stages.

Actully.. i think there is a good chance.. that this game stated out as a "mostly" single player game.. and then they saw how good it also worked in multiplayer

Seeing how the main objective of Splatoon is to conquer the map, an open world campaign will get boring quick.

I can imagine messier variation of jet set radio. Racing around, tagging everywhere with paint, as and evil mob of cleaners chase you down scrubbing floors as they go.

That would be amazing but... I doubt it.

Best Idea I've heard so far though.

If they make it work, then sure...
If it's open world because open world is trendy, then no...

I don't see why being the next TItanfall would be bad. The game had good reviews, sold more than 2M on XOne, comparing to PS4's top sellers would stay in 4th place, very close to the top 3 and its on a console with a much much smaller install base. Also it sold more than any PS4 exclusive.

I don't have X1 nor have I ever owned a MS console (though my brother did) so I'm not pro MS, but it don't understand all this aversion against Titanfall. And I bet that comes mainly from Sony owners which are the majority around here.

 Splatoon is not an action platformer like Jet Set Radio so I doubt that will ever happen.. The idea does sound cool though..

If you mean like jet set radio or De Blobs setting, then i agree (most especially De Blobs setting)

You're right that its not a platformer, but from the previews I've heard the players seemed interested in the freedom of movement provided by the mechanics. I could see a little bit of puzzle based pseudo-platforming marking its territory in the game.

(Wasn't there even a wall-jump for the squid demonstrated briefly for moving narrow gaps between painted walls?)

I think I've seen something like that for the squids, yeah, so maybe this idea could actually work! Still seems very unlikely to happen if you ask me..