I bought the 65737 when it came out and got everything working perfectly and ended up with 6 pairs of nice active shutter glasses. I just recently upgraded to the 73642 which of course has the adaptor built in but still uses the IR emitter. For some reason i couldn't get the 3D to work. The TV was/is spectacular, and after 2 days of headaches I finally tried the glasses that came with the new TV. One has to buy a package with an emitter that comes with a pair of Xpand Mitsubishi glasses. I could tell it was better, and after some experimenting I changed the TV settings to "Reverse" instead of Standard.
After that, the 3D was flawless. it's not the end of the world that I'll have to buy a few more pairs of glasses, but it amazes me that no one at Mitsubishi warned me of this, and that it doesn't seem to be common knowledge. It also doesn't make much sense to me. I thought the active shutters were pretty much the same, and I never heard of having to use Reverse for these glasses to work correctly on a Mitsubishi DLP.
Just curious if some of you understand what is going on here, and if it makes sense. There is always the possibility that something is wrong and that I just found a work around.