Jason Kaufman has written more about the Hispanic Society's apparent plans to sell Archer Huntington's coin collection long held at the American Numismatic Society: http://www.theartnewspaper.com/article.asp?id=16116 Another story about these plans can be found here: http://culturalpropertyobserver.blogspot.com/2008/08/archer-huntington-coins-to-be-sold.html
As Kaufman notes, unlike prior sales of Hispanic Society material, this sale would seem to potentially be at odds with the Hispanic Society's core mission of preserving Spanish Culture. Obviously, putting together a similar collection today would be very difficult, if not impossible.
Moreover, while there evidently is some possibility Spain may wish to purchase the collection, it presumably would only do so to repatriate it back to that country. That, of course, would do little to promote the appreciation of Spanish coins and culture in this country.
One further thought. While the Kaufman article focuses on some of the superlative pieces in the collection, no doubt the collection also contains many coins of modest value. Hopefully, the ANS and the Hispanic Society will come to some agreement that at least allows such coins to stay accessible to numismatists in the ANS collections.