Thank you all again.

I've calmed down considerably. It was just a surprise, you know? I had no idea this was apparently festering with him.
Our priorities are simply not his. We're working (a lot!), raising a family and trying to maintain a life that doesn't really involve our lawn.

And please note also that when I mention it being slightly shaggy, it's not even usually that way! His, on the other hand, looks like an immaculate green carpet.
I should also note that a family member of his owns a landscaping business. And regularly parks his (very large) truck (that partially blocks our driveway) in front of his house. (And a fire hydrant.) When DH pointed out that we could call the cops on that, he was told, "That's different!"

I want to, but on the other hand, I really don't want to getting into a ... match.
DH and I are making jokes back at each other about "Be like the others before it gets dark!"

(Cookies for you if you get the reference!) And I think I have him convinced to call the non-emergency line and talk to someone. I'd just like to get this on the record.