I'm going to do the popular thing and "use one of my lifelines and ask the audience".. <g> Too many questions to answer in one post.... but I'll try.

"can an Atlantis chip that is not notched be redeemed for cash from the Gaming Commision?"
I'm told the answer is YES; with interest!

"would the Commision release this information and can it be determined how many chips are outstanding, the denominations and the various obsolete casinos that would be involved. It may then be possible to place more realistic values on these chips."
I'm not 100% certain if Gaming would release that information or not... nor would some of that information be very meaningful. Collectors determine what they want to pay for certain chips depending upon availability. If outstanding chips are not in the hands of collectors or dealers, but are residing in dresser drawers of uninterested parties, the number of chips outstanding becomes a moot point. (I'm sure many will disagree with that statement.... ) 100 outstanding $1, $2.50, $5 or $25 chips would have less of an impact than 100 of $100 or $500 chips... as there are not that many collectors of the higher denominations. A few hundred outstanding would be more significant.
The lower denominations would be absorbed into the hobby with not too many waves. It would take a long, long time for the higher end chips to be dispersed.

"Could Brighton chips be in the cage at the Sands?"
Anything is possible, but I doubt it.

"Is this because the Sands may have purchased the Brighton and all of it's liabilities. Would the Sands cash a Brighton Chip? Or would you return it to the Gaming Commision?"
I'm sure that Sands would still cash a Brighton chip..... but what collector in his/her right mind would do so?

"Are BOA chips at Caesars?"
I would suspect they are. It's still the same property. Boardwalk Regency was also CAESARS Boardwalk Regency. I do know personally that Caesars Boardwalk Regency roulette chips were put back into use very briefly for just a weekend or so, less than a year ago, to test some automatic sorting equipment.

"Are Playboy, Hilton, and Harrah's Trump Plaza chips all destroyed"
Just a guess, but I would say yes to the value chips. Unlike (Caesars) Boardwalk Regency, these properties are no longer in existance and could not be re-introduced for play, so why would the casinos want to keep them?

and my only question is...."Would the Gaming Commision tell us?"
I would suggest that you write to them and find out what they have to say.... There are many club members who work in the casino industry and as far as I know have been unable to get that information.

I'm glad I'm leaving for the weekend. Somebody else can play with all the counter-responses that I'm sure will be forthcoming. Will check back in on Monday.... See you next week Chuck.