What are the differences in a dng file converted using version 2.4 vs 5.6 other than camera profiles for new supported cameras. Is there any quality advantage? e.g. I have an Oly E20 which is supported in ACR 2.4. If I converted in 2005 using version 2.4 to dng have I lost out on the oportunity to convert with the latest converter 5.6? If so what?,
I recall reading something new in the version 3.X or 4.X??
The big difference would be that the DNG specification has been incremented (to 1.3) and includes a number of aditional functions. As you noted, this includes the new profile specification. Another very useful addtion is the raw data verification hash (MD5 digest) which CR and LR can use to detect corruption. There are other changes detailed in the DNG specification which can be found here: http://www.adobe.com/products/dng/
As for a quality advantage, I guess it depends on what you're definition of that is? The original raw data won't be better per-say but the container certinaly is. You can always run existing DNG's back through the converter if you want to update them.
Hope that helps-
Thanks for the heads up.