I take too many, so much to the point where I have an entire folder dedicated to all of my ACNL screenshots. It also doesn't help that I haven't sorted out all of my screenshots yet, haha.
I used to take a lot of pictures when I first started playing. Now it's pretty much only when something special happens. I save my pictures on my laptop so I have space on my SD card. I think I have 20 some odd folders of pictures with 100 each in them.
I take them sometimes. Defintely not as much as I used to. I pretty much only take them if something new or funny happens. And I also take them when I have a villager over c:
I take pictures of me catching cool fish, villagers doing cute stuff, weird things, etc. My SD card is full, and I only have taken snapshots of ACNL. I'm a bit embarrassed...