That's the problem I had with my old Galaxy S4. I ended up buying a much weaker phone that had an actually fuctional standby. I learned my lesson from that experience, so when I bought my 3DS, I also bought a 5000mah extended battery. I can leave it unplugged for days, now. Pity that won't be an option with the Switch.

Keep in mind Mario Odyssey is going to be 60fps, and probably push the system to the limit as well. I'm guessing it'll only be indies and small games like Octopath Traveler that last more that around 3hrs.

I don't think so, I know is 60fps but is still not a gigantic world constantly loading more and more land when you walk, and it doesn't  seem to have anything close to the advanced physics and wind simulation of BoTW for exemple, or the level of detail, I think is probably less intensive for the hardware but we'll see.

i read that it only dropped 2% over 8 hours.

Typically one, sometimes more, sometimes less

For nintendos sake I hope the NS isn't in any way cmpared to the Vita.

Three hour limit with an open world game....seems less than ideal. At least there's the option to just play it at home proper.

I think it was at default brightness AND with Wifi functionality on and things, there are a number of factors that effect battery power 

they squeezed in the biggest battery they could in the Switch guts. People have to be realistic, there is no portable handheld system on the planet currently that can run an open world game (without melting) for like 5 hours

Well this is what i expected, wont bother me since i dont plan to play it on the go, for me its all about that console experience (im not a fan of handhelds).

That is very good to hear if it's true! I like to just have my 3DS lying around next to me to pick up and play a little bit every once and a while, and I'd like to do the same with the Switch.