We do nothing to our lawn. It looks fine. Of course, we have no neighbors directly next to us on either side, just woods and a big weed field, so it would look good be comparison anyway. Glad I don't live somewhere that would require actual lawn labor!
We've got woods to the back of our property. My problem is that we also have about 10 huge oaks in our back yard. So growing grass is almost out of the question.
I'd let it remain natural, but the kids need a place to play. Plus, without vegetation, when it rains, it all drains down and floods my neighbor's yard.