I also noticed that jwickis's playlists were capital letters - they're a bit wider, so it's not surprising that they highlight properly (I wonder about 'I', though). The wider lower-case letters (f, m, v, w, x) get highlit.
So a workaround is to use capital letters. As someone with a Unix background, they are a bit alien to me

, but I'll consider it. Upper case is generally harder to read, with the letters being more similar in shape than the lower-case letters are - there's a reason most road signs are in mixed case...
Of course, this is only a cosmetic issue, and it doesn't actually ruin my enjoyment of the player...