@larryi - that's an interesting test with surprising results. I mean, I was familiar with VHS tapes, but DVD's still looked a lot better to me when those came out.
I'd like to see more details about that researcher's test of 15 years ago, as I'd have to question how he converted those 'high quality recordings' to 'CD quality recordings' (to me, CD's are plenty high-quality). After all, there were some really rubbish sounding CD's through much of the 80's, especially. It's a real art and skill, mastering music for CD's and other media.
I'd also be interested in knowing how the test subjects did this listening - if it was on crap earbuds or on a crap system, no, I probably wouldn't be able to tell the difference, either, or might prefer the mp3... If it was on a good sound system (and it may have been, I don't know) or quality headphones, the results might have been quite different.