Yes, this is referring to Blockbuster on Demand. You should've recieved an email that stated the following:
"We have some good news and some bad news. The bad news is that, as of 3/31/12, the Blockbuster app will no longer be available on your Western Digital Player. We are updating our technology platform and will not be able to continue supporting your device.
The good news is that you can still stream your movies on your PC or MAC and other supported devices.
We offer many other ways to watch the movies you've already rented or purchased:
Purchases: Your purchased movies will still be in your Blockbuster On Demand Library. You can watch them on any of our other devices, or stream them via PC or Mac. See a list of supported devices.
Rentals: Please watch your rentals by 11:59 PM ET on 3/29/12. If you don't watch by then, you can watch on another supported device or stream via your PC or Mac. See a list of supported devices.
We are hard at work improving our service and plan to add new features and devices throughout the year. Thank you for being a Blockbuster customer and we apologize for any inconvenience this transition may cause.
Your friends at Blockbuster"