This is by far my favorite place to see a concert. You get to be outside around a really nice cared after area while enjoying an event. I've been numerous times with the most recent this past June to see Kenny Chesney. He put on a hell of a show and packed the venue. Some tips:
1. Get there early if you don't want to walk far from your car to the venue.
2. Wear tennis shoes or flip-flops because your shoes will probably be ruined and you need something comfortable to walk in if you are parked in the fields.
3. Tailgate beforehand and drink outside the venue. You are paying $10+ inside to drink, which is stupid.
4. Get there early and tailgate with all the other crazy, fun people. It is an experience you will never forget.
5. Do not be in a hurrying leaving because traffic is terrible and they have nobody directing cars out so it's just a big cluster.
If you take the advice I gave and the other reviewers then you will have one hell of a time. I prefer to sit in the pavilion but the few times I've sat in the lawn I've still had a great time. Just make sure to bring blankets and sit up near the back if you get lawn tickets.