I have downloaded from the B&W Society of Sound collection a few albums in 24/96 (or 24/88) that I also have on CD, and then compared them via my Squeezebox Touch. I'm confident that I hear an improvement with the higher-rez vs 16/44.1 ripped CDs. I also think that as streaming technology improves (and/or my budget
, then the differences will become even more apparent.
But... hearing a difference between 24/96 & 24/192? I kinda doubt it. I tend to think that the difference I hear vs CD is due to the increased bit depth (24 vs 16) moreso than the sampling rate. But either way, I think given the choice between CD resolution and Hi-Rez, I'd always opt for the better fully believing the difference is there.
Caveat - there have been rumors that some of the Hi-Rez content available is nothing more than upsampled CD rips. That would suck if true. Right now, my sources of Hi-Res music are B&W, HDTracks, & Linn.