A pretty good solution is to use an optical digital connection for your sound to the receiver and use a HDMI for the video, running the cable direct to the TV or projector bypassing the receiver when you are watching 3D. You get Dolby Digital 5.1 sound or 5.1 DTS and it sounds good. You don't get the lossless sound formats that way, but you save hundreds of dollars. You can use HDMI for sound and video through your receiver for any non-3D material and have lossless sound then. You keep your HDMI connected to the receiver most of the time, but when you want to watch a 3D Blu-Ray you unplug the HDMI from the receiver and plug it directly to the Blu Ray player. You might also have to tell the Blu-Ray player to output sound through optical cable to your receiver if it can't just always be doing that.
You'll find you can hardly tell the difference between Dolby 5.1 and lossless sound, if you are like me, and I sure like sound.