FYI, Heritage Auctions is beginning to list info on lots for its May 2011 auction including some casino chips.
Pictures & opening values not posted yet, but titles for 11 casino chip lots are there. (I don't know if this is all the chips, are if others are coming.)
Auction to be conducted on May 21 in Dallas, per their website.
If you want to keep tabs on it, simply go to HA.com and enter "casino chips" in the search box.
(None of the lots are mine.)

Titles to the 11 lots posted thus far are ---

Pequop Casino $25 Chip, Wells, Nevada
Harvey's Wagon Wheel, Lake Tahoe, 9th Series $25 Chip, Rated R-9
Alibi Club, Reno, Exceedingly Rare 1st-And-Only-Issue $5 Chip
Dunes 14th Series $5 Chip, the Popular "Marquee Issue."
El Cortez 6th Series $1 Chip
Flamingo 2nd Series $5 Chip, Rated R-6
Golden Bank, Reno 6th Series 10-Cent Chip, Rated R-10
Dunes Hotel 5th Series $1 Chip, Rated R-8
Club Bingo Beige $100 Chip, the Notorious "Measles Issue."
Main Street Station First Series $25 Chip, Rated R-8
Cal-Neva 6th Series 10 Cent Chip From Reno, Rated R-10