This was a very good test. You, sir, picked a very good song for this test (in the sense that it’s very hard to tell the difference). It took me several listenings to pick out the correct one (which i did manage).
Now i want to point out a few things here.
First of all, you didn’t specify how the encoding was done and with which encoder. You see, 128 kbit MP3′s are typically ALWAYS encoded in Joint Stereo by most modern encoders, while 320 kbit MP3′s can often vary between normal …

The first time through I got it wrong also. I then read all the comments in the blog and listened to both a second time and still couldn’t hear the difference. Then, I listened to them the 3rd time and this time put my head exactly in the center of the 2 laptop speakers on my Toshiba – and then it became apparent. The 1st track has slightly almost unnoticable more clarity but more important it has “depth” and the second track doesn’t.

A while ago, I decided to switch to mp3 music instead of cd’s, so I painstakingly ripped all my cd’s (500+) onto my computer. It’s much easier finding albums on a computer than it is sifting through piles of cd’s only to find out that I put the wrong cd in the case that I was looking for. Plus, I really love “super random” play.
Anyways, I did all my encoding at 128kbps.  After I finished (a week later!), I was talking to a friend of mine who had …