As someone who has spent many, many hours behind both analog and digital recording gear, he is my point about the high resolution format. If your master was done in 44.1/16, it's not going to really get any better then that. We can reprocess the 44.1/16 to higher speed, and word length, but zeros and ones are going to be extrapolated (depending on software used) and while it could be a guess, the fill in the blanks are still a guess, even if they are probably correct. If the music is recorded in a higher digital resolution, like 192/24 to begin with and mastered down to the redbook 44.1/16 that is one story, and if it's downloaded to a computer in it's original, mastered state of 192/24, now we can compare 44.1/16 to the original 192/24. And the only thing that will be proved or not is if an actual hi res master sounds better then it's reduced redbook cousin. I think it also depends on the music, the recording engineer and the playback system. A remastering of a high quality analog recording to a high resolution is a different matter (and really makes sense).
Wayner 
I am a big fan of the Grateful Dead. One of the somewhat disappointing things to keep in mind is when they switched from analogue reel to reel recording of their shows to digital. this does mean that there will be no better sound quality available from the 16/44.1 files, or any files recorded like that. The "golden age" of recording is from the late 1950's to the late 1970's when the recordings were high quality analogue.
I see these threads pop up from time to time. I am totally sold on higher rez recordings. I think the Raising Sand example is not a good one, my understanding is that the hd tracks is simply an upsampled version. I don't trust HD trax or their sources because of that.
I have many 24/48 and 24/96 live recordings of many different bands. I find the 24 bit to make more of a difference than 48/96 though there is some improvement there.
To me higher rez means a more 3-d soundstage, creamier vocals, tighter more tuneful bass. Though I know that there is plenty of signal to noise ration with 16 bit in theory, the 24 bit seems to have a deeper background. I can really tell this with audience recordings where the low level audience chatter is MUCH more defined with 24 bit sources.
If you can't hear it, fine. My I am just deluding myself. I have been told that many times. 16 bit recordings, when done right, can sound very good. I don't doubt that. But for me, 24 bit is where it is at!
If you really have any doubt check out any of the new King Crimson DVD-A discs.
