There are 1.3 certified cables, but what does it really mean?

For video quality, it doens't mean squat. The 1.3 HDMI interface, while it offers deep color capability it is not something that is currently available on discs to my knowledge.

1.3 also adds the ability for bitstreaming of HD audio codecs to capable receivers if you want.

But, realistically, the difference between 1.1 and 1.3 is pretty much going to be found in audio, not in video.

If you don't see a significant video quality jump with certain BD discs, then there are any number of reasons for this. One of the most obvious is that the disc itself was poorly encoded for video and simply doesn't look as good as some of the other titles which are out on the market.

With an audio specific disc, you likely may find very basic video of low quality, but the audio itself is like a HD audio codec which is far superior to CD, and likely rivals that of SACD and DVD-A formats.

I recommend that you take a look at reviews over at http://www.highdefdigest.com for some disc reviews prior to purchasing them. Some are outstanding... some are not.