How do YOU decide what 3D movies to buy? Or will you buy anything in 3D?

[Dnsmills]

I've looked through some people's list of their 3D blu-ray collection and it seems they have just about everything under the sun. While I'm new to the game and I'm just now beginning to grow my collection & there's a number of discs on my must-get list, there are some that I don't feel the need to own JUST because they are in 3D. Do you try to grab up every 3D movie/documentary you can find or do you pick & choose? I don't feel the need to own EVERY standard 2D blu-ray so I also don't feel the need to own EVERY 3D blu-ray just for the fact that it is 3D. Just wondering what other people's perspective is.