There was a time when I used screen protectors on all my devices. My Apple Newton Messagepad 2100 had a screen protector. Then, any other device that had a touch screen got a screen protector. This includes my Palm Pilot, the Casio Cassiopeia E-125, HP/Compaq iPaq, the Treo 700wx, and more recently my HTC XV6800.
I've started moving away from screen protectors on some of my other devices. For instance, my Samsung Q1 Ultra UMPC doesn't have a screen protector. I've been using this device for over a year and it doesn't have a single scratch on it. I also haven't used a screen protector on my Lenovo Thinkpad X200 Tablet. No scratches.
So. my XV6800 needs a new screen protector. There are several different types and I've been using the original one that came in the Verizon box.