Technical data is all well and good but, as has been mentioned a fair few times, it is your ears that you should trust at the end of the day. If you can't hear the difference between formats, more power to you, you can save a whole lot of disc space and more "fully" utilise your portaplayers.
I am not what most people would call a "bona fide" audiophile. I lack the funds for high-end equipment, I think that my 175 Euro Sennheisser HD 25 II's are great (they are the most expensive earphones I have owned to date), am reasonably happy with my Skullcandy Aviators (though they are somewhat lacking in bass impact), and often enjoy the sound of my $99 Marshall's (who, at risk of sounding pretentious, have "personality" and make the music sound "come to life" to a certain extent). My stereo is, by today's standards, very dated, and my DAC is an onboard laptop sh*tbox. Furthermore, my higher frequency register is slightly impaired.
That being said, I have noticed that in many cases, (probably not all), the base sounds fuller, richer and has more impact in lossless formats. The fundamentals shine through. In chewy4's DBT I scored 2 out 2 (there are three but I skipped one) based almost solely on bass response. It's true that the difference isn't enormous between lossless and 320kpbs but is is there. And if you have higher quality sound sources than I do, which many of you probably do, then those differences should be more noticeable.
So if you, like me, a fan of electronic music you are probably into those lovely warm bassy sounds. They just sound better in lossless formats. Just my 2 cents.