All: thanks for your responses, below are some comments:
@AntiM: I've been to Bonneville and like the Black Rock, Bonneville needs to have a race track prepared for automobiles. I'm not sure if there is much land sailing on Bonneville, at least I have not heard of any. Ivanpah is a better surface for land sailing: cars and trucks are no longer permitted. Yes, I can land sail elsewhere, and the land speed record can occur elsewhere. Having a discussion about the negative impacts as compared with the positives of Burning Man is a good step. Can we all admit that Burning Man is no longer "Leave No Trace"? My feeling is that the dunes will eventually impact Burning Man quite a bit. In 2008, bicyclists had to follow vehicle tracks. El Nino is in roughly 7 year cycles. My gut feeling is that we will have another dry winter. If this is the case, the Burning Man 2013 will be impacted by the dunes, so maybe some research as to whether it is getting worse is in order. I don't see Lake Lahontan recovering unless we have an ice age. The progression of a dry lake bed to a dune field is a natural progression, my position is that Burning Man is greatly accelerating that process. Another scenario is that the Black Rock Desert is found to be damaged and is closed off to vehicle traffic like Ivanpah. If this happens and we could have prevented it by keeping Burning Man at 50,000, then what would that feel like?
@LegendZero: Your point about the increase in the number of photos taken of the desert is well taken. How come these dunes have not appeared on any of the other nearby playas? As I've said, it is impossible to prove a negative. The first dune picture taken by James T. Neal was considered unique enough to be included in a paper about playas. I would expect to see other pictures. About Bonneville, Wikipedia says that the salt flat is shrinking because of the salt mining for potash production. Also, the railroad causeway has changed the water distribution. So, I'm not sure if Bonneville will be useful for very long for land speed record attempts.
BTW - the black rock desert is not a salt flat, it is a dry lake bed. There is some salt in the playa, but not very much. Check out Wikipedia's dry lake page:
http://en.wikipedia.org/wiki/Dry_lake_bed@SnowBlind and trilobyte and Isotopia: Thanks for reading and the positive comments.
@oneeyddick: Actually, I was shot at, not shot. My wording was poor. This was 1992, there was no fence etc. I was camped with my wife and kid on a hill and we woke up to someone target practicing on targets just below us. Bullets whizzing by etc. I was tempted to return fire, but decided it was a mistake and snuck over to the car and honked. The great thing was that the guys came up and were basically just like me: looked like me, drinking Sierra Nevada at 7am etc. The were apologetic and I realized it was a mistake anyone, including me, could make.
@kiss-o-matic: My proposal is that Burning Man buy land, perhaps an abandon open pit mine, and use it. If trends continue, bicycling will be very difficult in BRC. Burning Man does not spend much money on art, maybe when the non-profit kicks in, the books will be more open? One sort of modest proposal I had was to pave the playa. It would not cost that much and it would prevent the dunes.

@skyhawkecks: Heh. I'm no BRC fan-boy, but BRC has made good decisions in the past. No vending is another example. There are plenty of less than stellar decisions, the ticket fiasco being one.
@EspressoDude: The short answer is that in my experience, much of the dust for the dust storms comes from the road in to the city. Evidence: 1) The dust is worse around 6:00. Last year, I was camped at 3:00 and portal and we were out of much of the dust. We could see the dust just on the other side of the Esplanade though. 2) I've been land sailing south of the city when dust storms have started and been in clear air.
Another issue is that the winds tend to move the dust around the desert throughout the year. The strongest winds are usually from the south, but winds from the north are common. The dune field is largest NNE of the city, There are the least dunes in the wettest part of the desert because the water smooths the dunes out. The water on the playa often moves with the wind, and if there is ice, that will move as well. Thus, the smoothness in the low part. Check out Google earth.
@jackass: I contacted James T. Neal about the photo in the 1970 paper and he said that it was taken in the early 60's. My gut feeling is that the picture is actual of Michael Heizer's land art piece and that Neal's recollection is mistaken. So if that is the case, then yes, the dunes were caused by hippies

However, I need to take Dr. Neal at his word, but the coincidence of the locations of those dunes and Heizer's land art piece is remarkable. Check out the site and look for the Google Earth KMZ file.
@BBadger: I agree that the proof is in the anecdotes. Like everyone, I have some stories, but don't want to drag others into this. Point well taken though.
A few further thoughts:
Would your rather go every other year to an event that was 35,000 (or 50,000) people or go every year to a 70,000 (or 100,000) person event? I, for one, find the highs at Burning Man to be quite high, but the lows to be quite low. Many of the lows are brought on by the sheer number of attendees. 4+ hours to get in, all day to get out. Wrecks on a 76 miles of two lane black top. Dust storms that occur earlier and earlier in the week. More and more spectators. Maybe it is time That Thing In The Desert to stopped growing? If you don't think it should stop growing now, then when should it stop growing?
Most of the comments have focused on the dunes and land sailing. What about the first two components of my appear: Burning Man broke the rules (which is under appeal) and got rewarded and that the BLM has never done an annual performance evaluation that is mandated by the SRP process. Does anyone really want a larger event? I think that getting a review would help BRC ensure that the event continued? Any thoughts on these two topics?
Anyway, thank you all for reading and being civil or at least humorous.