I'm a bit skeptical about the Switch. However, I can tell I'm one of those gamers who likes to play longer, AAA-like titles on the go. I commute almost 2 hours and this is a perfect time to play on the go. I spent lots of time with the flagship Vita games ( Killzone, Uncharted, Gravity Rush ) and at some point, such games ran out. So my interest in Vita did too. I don't mind to play a boss fight on the train if only I can quickly suspend the game and resume later. Being able to play the same game at home ( without worrying about battery life and on the big screen ) is also something tempting. But there's one thing which doesn't convince me enough - Nintendo. I played old Nintendo games, I acknowledge their importance in the video games history but I don't find playing yet another Mario or Zelda fun anymore. They had titles that came up to be good but it was just a handful of games that could hook me in and make me spend hours playing.
Well, there's this other "competitor" - mobiles. I usually have a gamepad with a clip ( MOGAPro ) that not only can turn my mobile phone into a small handheld gaming console but can also extend the battery life a little bit. I played a couple of games like that and it was a really great experience. Shame there are only few that support it. So this is a field on which mobiles won't be any competitor to Switch. Despite the mobiles can support a controller, the games rarely use that. The mobile market took a turn at some point towards 'free-to-play- experience and titles like old Gameloft games ( "Modern Combat", "Gangstar" etc. ) don't seem to appear anymore. Yeah, I know these were "cheap ripoffs" but also it was closest to what could be considered "a console experience on a mobile device". That's why I found Vita so appealing.
So here, in the middle of this, the Nintendo is. It's very important question who is a target audience for Switch. I think people like me could be the audience if only Nintendo lets more variety into their titles. Although, it's still too early to make any judgments on it.