I am attempting to compile a list of numismatic auction sites, complete with pros and cons of each. I may use this information to write a brief article or comment for submission to
Coin World. If nothing else, this thread can be used as a guide for forum members.
As a means of comparison related to selling on each of these sites, consider the following scenario: selling 1 coin with a starting bid of $0.01, 7 day auction, listed in two categories, two pictures, with no special changes to the listing (e.g., bolding or highlighting the title, etc.). The coin sells for $100.00, with the resulting payout equal to $100.00 - auction fees (listing plus final sale).
Sites are listed in alphabetical order. If you can add a site, comments on any of those listed, or selling payout calculations, please contribute! I'll update this first post with additional information.

---UPDATE: Been busy with "real life" stuff for a while, will finish this eventually.
---------------------------------------------------------------BidCoin (
www.bidcoin.com)
Pros: Specific to numismatic items
Cons: Low membership (649 as of 2/08/07), few auctions
Sales Payout: $97.77
Coinbay.biz (ww
w.coin
bay.bi
z)
Pros: Cheap or nonexistent listing and selling fees, mainly specific to numismatic items
Cons: Low membership (714 as of 2/08/07)
Sales Payout: $100.00
CoinsNCurrency (
www.coinsncurrency.com)
Pros: Cheap or nonexistent listing and selling fees, specific to numismatic items
Cons: Few members (78 as of 2/08/07), few auctions
Sales Payout: $100.00
eBay (
http://coins.ebay.com)
Pros: Large user base, large selection of coins
Cons: Many selling fees, some crooked sellers with overpriced and/or counterfeit items, multiple home-based slabbing "companies" can confuse unknowledgeable buyers
Sales Payout: $94.85
Heritage (
http://coins.ha.com)
Pros: High quality pictures, good merchandise
Cons: Significant seller's
and buyer's fees
Sales Payout: Difficult to determine, could use some help with this one.
Overstock (
http://auctions.overstock.com)
Pros:
Cons:
Sales Payout: Could not determine without signing up.
Teletrade (
www.teletrade.com)
Pros:
Cons:
Sales Payout:
uBid (
www.uBid.com)
Pros:
Cons:
Sales Payout:
Yahoo (
http://auctions.yahoo.com)
Pros:
Cons:
Sales Payout:
---------------------------------------------------------------Sites not specifically devoted to auctions, but with an auction component:
Coin Community (
www.coincommunity.com)
---------------------------------------------------------------Thanks for everyone's help!

Regards,
~neuron