They just display 'LOADING' or something like that while it loads your CD.
When playing CD's, they'll display track names on regular CDs that have CDText, and when playing MP3's, it will display either track name, artist or album name from the ID3 tags (you can press a button to choose which), or the file name if you don't have ID3 tags on the MP3's. I use CDex to rip my CDs to MP3 format, and haven't any issues with displaying track names etc.