New Screen Issue?

[MILH0U5E]

Please check out the pictures I took of my Sprint TP attached below. This has been happening periodically for the last few days, but has gotten more frequent. I've had this issue on 2 different ROMS, and at varying parts of the day. From waking it in the morning, after a soft reset, sliding the keyboard in/out, and now it just did it after I got off a call with Sprint (they are sending a new one).

Is this the beginning of something worse? Should I flash it back to the shipped ROM now, while it's still working? Or is this just a glitch with this phone that happens over time?

If anyone can provide any feedback I'd really appreciate it. As I said above, I'm getting a new one sent to me; but feedback on this may help someone else in the future.