I've got the purple lines on my display as well, but they don't really bother me. It appears to only show up on a bright/white background with a dark foreground (text, image, etc). Looks like some sort of shadow. Funny thing is I never really noticed this, so I didn't know to look for it until I saw this thread.

What I don't like is the screen's 16 bits per pixel. The gradients (e.g. the Nokia one when you power up the phone) look washed out. Hope this can be sorted out in PR 1.1.