I'm using Win XP, updated iTunes & QuickTime to most recent & using LW 5.2.13 & no problems with the user playlist showing in iTunes including music & video. Unlike LW 4, you do not see Library & user lists, instead you simply see the user shared playlist with drop down arrow.

* For the songs to appear in the shared user list in iTunes, it appears they need to be shared in LW. I think that means it operates differently to previous versions of LW which from memory showed all recently downloaded music. Under LW's Tools -> Options menu scroll down to iTunes options button & ensure share with iTunes is enabled.

Using another Win XP with updated iTunes & QuickTime & LW 5.3.4 Beta, the other account's LW playlist (one mentioned at of post) shows up fine as does the LW 5.3.4 playlist, and another from a mac computer.

Generally after installing/updating QuickTime you should reboot your computer.