Having had some time to mull the MOU over a bit, here are a few thoughts for what they are worth:
1. The decision is likely a victory, of sorts, for a prominent auction house. If memory serves, that auction house provided CPAC with a chart and back-up information that demonstrated that many extant Chinese artifacts post-Tang were never buried in the ground, but rather were handed down to subsequent generations. What CPAC or the State Department ignored, however, was an important second step in the analysis. For archaeological objects to be restricted under the CPIA, they must be "culturally significant." The auction house proposed a common-sense analysis for determining what is "culturally significant" and what is not "culturally significant." That analysis suggested that the question of restriction should be evaluated in light of the following factors related to a given object: the quality and state of the existing archaeological and art-historical record; site specificity, portability, and documentary importance; mass production and lack of rarity; frequent and long-term market incidence. This approach is far more thoughtful than simply banning anything old "found in the ground," but that is just what CPAC or State did in deciding to impose import restrictions on even common artifacts, like coins.
2. The AAMD decision to retreat from its prior "10 year rolling provenance" acquisition guidelines in favor of a 1970 date made the museum community's prior strong opposition to the Chinese restrictions largely moot.
3. Although the archaeological community will likely paint this decision as yet another "great victory," at least some are probably disappointed that the restrictions did not extend up to the 250 year old threshold under the CPIA. On the other hand, ending the restrictions at the end of the Tang Dynasty makes much sense from the perspective that many later goods were widely traded around the world. The most famous examples, of course, are Chinese porcelain objects.
4. The State Department bureaucracy is largely oblivious (or more likely uncaring) about practical concerns. The great similarity amongst cash coins of all eras was mentioned to State Department officials on several occasions. Yet, this practical concern about Customs confusing cash coins of different eras was largely ignored, as was the point that the minimal value of many such Chinese cash coins makes complying with the stringent documentation requirements "not worth the trouble." Of course, neither the State Department nor the archaeological community has to enforce or live by these restrictions. Rather, Customs and importers do. Wouldn't it be interesting to mandate detailed record keeping about the find spots, as well as the storage and disposition of archaeological finds like individual coins, and then see how the archaeological community would react?