The 3DS, is a good system but it has some features that have no use at least for me that is.
Nintendo Video - I thought it was going to be similar to YouTube in that you could watch anything in the collection on demand, but since it only has four videos at any given time pretty much makes the app pointless.
Face Raiders - Only tried it once. It's literally the only app that I have never opened more then once. Didn't care for it.
AR Games - I think I only used this once or twice, pretty much for the same reason as Face Raiders.
Nintendo Zone - This thing is absolutely useless due to how slow it is and how it is only usable at select locations. I have used it several times at McDonalds. During a busy day where I had to wait a good amount of time for my food, I was barely able to navigate around the system before my order was ready. Even sitting around after eating, I got bored of waiting for pages to load and gave up on it.
Swapnote - Fun to send a few notes at first, but feels just as gimmicky as the Wii Message Board after a few uses.
3D- I'm not interested in it but I can see why others like it.
Internet Browser- It's good for very basic internet usage (like email, Google search) but since I use mostly use the internet for complex stuff, I need something better. I probably only used it like 3 times since I bought 3DS.