In reply to:
I've watched quite a few movies in 6.1 and the rear center doesn't get a significant amount of dialogue (hardly any for that that matter).
Well I wouldn't expect too much dialogue out of the rear speaker, that would be kind of wierd.
But I do get sound out of the rear. Keep in mind that not all DVD's are encoded as 6.1. It also depends on whether your receiver or pre/pro has any kind of proprietary processing to convert 5.1 audio into 6.1/7.1. My Rotel 1066 has what they call RS processing that creates a matrixed back channel from any 5.1 source in fact it even works on top of ProLogic2 so I even get 6.1 sound for stereo sources if I want it.
But still, you'll get the most rear audio from a DVD that is natively encoded for 6.1, and particularly DTS-ES discrete, which is a true 6.1 format as opposed to a matrixed back. Compare the DD-EX and DTS-ES tracks on Lord of the Rings and you'll notice the DTS track makes better use of the back channel.
