I wanted my new ipod touch 4g to sound better than the original iphone 3g that I have but it simply doesn't come close. I bought the ipodtouch 4g as a remote and for surfing the web whilst listening to music through my AX and DAC!!! I do like the sound of the ipod touch 4g speakers when I watch my recorded HD videos (which are awesome). It might be something to do with the Cirrus logic sound chip, the Wolfson on the iphone 3g I think is superior sounding (plus the headphone amp on the iphone 3g has more grunt).
I use apple earbuds, PX200 or HD555 for my portable sources, and the ipod touch 4G as wonderful as it is with the retina display, a4 processor, hd video etc. doesn't sound quite as good as the iphone 3g. The iphone 3g has more bass and doesn't have a digital static sound like the new ipod touch. Plus it seems to have less conflicting frequencies. I do use EQ on the ipod and iphones cos they need it. In itunes with a decent Class A amp, the EQ is turned off.
Does it bother me. No! I don't bother with much music on my portable devices, because it never sounds good! I might listen to a state of trance on my ipod shuffle at the beach, but I mainly listen to podcasts. The apple ear buds are fine for most things. I want to protect my ears for when I really want to listen to loud music. If I am at home and want to watch a movie or listen to good music, I simply use my dac & HD650. The dac on the airport express and other Apple products sound mediocre (they are better than stock soundcards on PC but meeh).
I also don't believe in mini headphone jacks, no matter how good the cable is.
FINALLY
Please Itunes sell your music in Apple Lossless.