Don't tell him that there won't be any television, just keep other things going -- most ten year olds will be so happy to have you paying atttention and including them in the process that you won't need the tv.

Something like five years ago we had a major storm that blacked out most of Boston and the kids are still writing about how the best time they ever had was huddling under blankets with their whole families, playing board games during the day and talking together, telling stories, and singing when it got dark.

Also, if you don't make "no TV" a commitment, then you can decide that one "family all together video" to end the day is okay if you find your energy flagging without losing any face.

I might say "no video games" though. ;D