I didn't play much of Persona 4 when I got it back in the summer last year because I left to go teach abroad (I finished Yukikos castle and got a little bit further) but I got Persona 4 golden for christmas and it seems like the battle music has changed a bit. When I was playing the ps2 version I could have sworn I always heard reach of truth except for boss battles. In golden though I only hear that when I attack a shadow from behind and so I get the advantage. Every other time I hear I'll face myself. One thing I notice though is Yosuke is always attacking first if I do not hit the shadow first so I don't know if the music maybe changes due to which character is attacking first?
Another thing is Every time a battle ends I cannot choose randomly because I am able to see all the cards. The bottom of the screen always says one try left but it has been like that since the begining of the game.
Finally I remember on the ps2 version when I got to the floor where you fight shadow Yukiko a save point was added to the floor so I could teleport there and back from outside the dungeon, but in golden all I can do is teleport to that floor when I enter the dungeon. Although this may be due to difficulty since was playing easy on ps2 but normal on golden. I would check the ps2 version myself but I am currently in a different country.