Maddy Myers, writing for Polygon:

But the weirdest part of the reveal video, in my opinion, is the implication that the Joy-Cons can be used as a mouse.

This was already rumored, and if I hadn’t seen those rumors, then I might not have understood what I was looking at during the portion of the teaser that depicts the Joy-Cons sliding around on a hard surface like a cute lil’ mouse. Because of those rumors, though, I’m now convinced that this is a thing and the Switch 2 will include this feature. The video specifically shows the Joy-Con mouse position as perpendicular to the surface its on. The new Joy-Con mechanic is further cemented by the part of the video that shows a Joy-Con on its side with a section that really looks like an optical mouse light. [...]

But this is Nintendo, and Nintendo consoles almost always have a gimmick. The gimmick isn’t always good. Although there were a couple of games that made excellent use of the Wii’s motion controls, I can think of plenty more that were deeply un-fun. Then again, the Wii U’s gimmick — its tablet — paced the way to the first Nintendo Switch, the super-adaptable console we all know and love. So you really never know.

I’ll just say that Nintendo’s controller gimmicks are usually good, so if the new joy-cons can be used like mice, I’ll bet it’s in an unexpected way.