Not trying to start a DTS/Dolby argument at all. I notice on Blu-ray titles that DTS MA has 7.1 a decent amount of the time (not always of course). I guess where my question is is Dolby talks all over its site that it can theoretically go beyond 7.1 and yet to date not one dolby truhd 7.1 title to date. It sounds like a few companies have done a 5.1 EX truHD track but they are not even advertised as such. Reviewers do not even bring this up. Have never seen a review state TruHD EX. Is there a limitation to TruHD?

No.

Dolby Digital EX is not a true 6.1 format, as the rear channel(s) are matrixed from the side l/r channels, similar to the way a L/R feed is matrixed into L/C/R/S(left, center, right, surround) via ProLogic or ProLogicII. When a movie is encoded in DD-EX, a bit flag is set, telling the decoder to send the surround mono signal to the rear channel. Because of this, there is no need to encode the signal as 6.1. You can also force most any 5.1 sources into the DD-EX decoder on most receivers, giving you 7.1 channels, from a 5.1 source.
The TrueHD codec allows much more than what's currently encoded. It's just not used. TrueHD supports 24 bit, 96 kHz audio channels at up to 18 Mbit/s over 14 channels (HD DVD and Blu-ray Disc standards currently limit the maximum number of audio channels to eight). It also supports extensive metadata, including dialog normalization and Dynamic Range Control.(thanks, Wiki...)

exactly my point. How come no TruHD has gone beyond 5.1? If something is beyond 5.1 they use DTS HD MA. I know how EX and such work. Just wondering why TruHD has not gone beyond 5.1

exactly my point. How come no TruHD has gone beyond 5.1?

How many movies are mixed for cinema release at greater than 5.1?

Answer: Less than 0.01%

How come no TruHD has gone beyond 5.1?'Shinobi: Heart Under Blade' (http://bluray.highdefdigest.com/397/shinobi.html) is TrueHD 6.1 and 'Nightmare Before Christmas' (http://bluray.highdefdigest.com/1207/nightmarebeforechristmas.html) is TrueHD 7.1.

Sanjay