I bought two pairs of the CR-3500 Samsung glasses for my D7000 I just bought in March. Have had them for two weeks. One pair went dead after about a week. One side wouldn't kick on when 3D went active. Pairing and everything worked, one lens just wouldn't shutter. I just took that pair back to BB yesterday, now today, my other pair stopped- same problem. Left lens won't shutter.
However, I think I figured out why. At least with the latest pair, I had just cleaned off the lenses. I was very careful, used a microfiber cloth with just a tad bit of dampness to it. However, I've read online that you shouldn't clean both sides of the lenses at once because of the layers built into the lens. Now I was very careful and didn't hold the glasses by the lens or anything but that's clearly what happened to break them.
Now, seriously? $70 or more for a pair of glasses that you can break by handling them more gently than you would a pair of RayBans? I think that's a bit ridiculous. Still, at least I've learned what the issue is. I know I had cleaned the other pair before they broke. Be careful with these glasses people! Again, I think that's a ridiculous quality of build, but it is what it is.