I came here for the NHRA Finals on Sunday 10/16/11 and I had a great time. The last time I was out here was about 10 years ago for some Top Fuel Hydro races and honestly, not a lot has changed (except for pricing lol).
Also I think every ticket is eligible for pit area access now. Years ago you had to purchase a pit pass if you wanted to check that section out. If you do decide to visit the pit area be sure to stand behind a Dragster or Funny Car when they start it up. Its one of the coolest things you'll ever experience although its not recommended for the faint of heart. Once that NitroMethane fills the air around you your eyes, nose and throat immediately start to burn. It wears off pretty fast but its funny to see everyone running towards fresh air while coughing ( I won't lie, I was one of them).
My overall experience was amazing although its probably better to go during the February races, due to the fact that its still pretty hot out there in October.
Be sure to bring enough cash because everything is pretty pricey but thats to be expected. I think a large beer was about $9.50. GEEZUS!!! Oh and also plan on spending a good half hour trying to get out of there after the races. If you're not in a hurry to leave try to stick around because traffic is a nightmare right after the final race. You can waste some time by going down on the track, which, by the way is really, really sticky (one of my shoes almost fused to the track :D). Or you can buy some discounted food and drink but its definitely not a good idea to leave right away.