Here's Nick Southall's Stylus column about this, in case you haven't read it.
"Bill Drummond’s not alone in his grumpy musical fug. A little while ago Jarvis Cocker edited Observer Music Monthly. Part of the result was Drummond’s column, and another was this roundtable discussion about 'what music is.' The conversation is essentially a load of old farts moaning about why they’re not big cheeses in the music industry anymore (it’s because they’re old) and complaining about Busted as if they were any worse than The Osmonds or Take That or The Beatles pre-1965. Paul Morley particularly bemoans overconsumption, iPods, and the ease of digital music."
I read this too, and drew a similar conclusion (altho, interestingly, some of the complaints are pretty similar to a lot of the sentiments that fly back and forth on Dissnesus, too).
That said, I think it's possible that Drummond is both reactionary old fart and making a reasonably decent point with No Music Day. Not everyone will get it, and yes, it will be a nigh-on logistical impossibility to avoid music (in any given metropolis, at least).
But I think it's a lovely idea, and I'm gonna give it a go.