Mr. Blinky is the clock on the bottom left of your screen that reminds you 5 mins before the start of a program that your DVR will be recording something. The 721 has an option to disable this, and I held hope we'd get the same thing on the 508. Didn't happen on this release
I like Mr. Blinky, too, but one thing people don't like is the fact that if it activates when you're transferring something to VCR, the indicator appears on the tape. In such cases, an option to diable it would be a good thing. It's possible to press the "cancel" button to disable it, of course, but that means baby-sitting the PVR during the process.