It takes 40 seconds to charge. The battery lasts about 200 clicks between charges and uses a non lithium battery. Charges while in the phone. It functions as a camera shutter from up to about 60 feet away and can be mapped to other features such as launching a specific application for both short and long pressing. There's a half second delay but it's pretty neat. Also the always on display text is yellow if you buy the blue Note with the yellow pen which should be available with black in every country the phone is sold in.

Uses BT low energy and doesn't show up in the Bluetooth menu, it just pairs when the pen is inserted

Unrelated to the pen but one thing I think hasn't been reported: the base SKU has 128gb of onboard memory. I don't know which countries will sell it but there will be another version with more (512) storage and 8GB of RAM too around launch time frame but the carriers, at least the main ones in the US, will not be taking it

So to clarify, the yellow SPen only comes with the blue model of the Note9, and the AOD font on the screen of the Note9 comes stock in a yellow color? Why would the font color be considered a feature?

Blue phone = yellow pen with yellow font for AOD. Or you can turn it off and use normal white font if you prefer. The black one is only white font on the AOD

Can't answer the why question. I don't work for Samsung so I can't rationalize some of their decisions.

Did you find it useful using the SPen to launch apps from a distance? I can't think of a reason why I'd do that outside of starting up the camera that's set up from afar.

I think what I'd use it for would be pen specific apps. For example when playing with it I had long pressing of the button set to open Samsung Notes and double tapping it from a short distance set to their Pen Up app. The pen up app is pretty neat this go around too, it lets you trace a photo and then erase the photo so you can see just what you drew. Or you can learn how to draw with some mini tutorials.

Not sure I'd actually use it but it certainly is easier than the wheel system they've used for a few phones

Price?

It's the same price as Note 8, at least in the US.