Sad day. I always enjoyed their music and though they were in some circles thought of as a "parody" of the Beatles, they were genuinely very talented, made good music and had their own style. Their tv show was good for laughs to, when I was younger they used to show episodes on the "old" Nick at Night.
I just met him a few months ago. Really nice guy. He was still touring and seemed to be enjoying himself. I didn't see this coming at all.
He was doing a question and answer session when a girl (probably around 5 or 6) asked him if he could sing Daydream Believer. Right then and there he sang the whole song. It was a nice moment. Even though I hadn't really listened to their music since I was little, I couldn't help but smile during that song. That's what the Monkees did: Make people smile. He'll be missed.
Funny enough, there was a Monkees joke on Modern Family last night. It was subtle, but it must have been filmed months ago and was just an odd coincidence.