While the sales data is certainly encouraging, and indicate a robust domain market, particularly in the US, I think some are mis-interpreting the "domain with content" data. Escrow.com are a huge company that do escrow for everything you can imagine on Earth (and well some space things too!). They do collectables, real estate, domains, works of art, businesses, etc.
It is possible I am wrong, but having read both the press release for this and their longer report in January that started the series, I am pretty sure that any kind of a site or online business is considered "domain with content". So it is not that someone can use Wordpress to add a bit of content, and get 4x as much for the domain name. The 'domain with content' includes some that are just a domain and say a reference site content, but also includes a variety of online businesses where the domain name and business are sold as one.
Therefore, I think for the world of domainers, the more applicable figure is the $2500 average and the sales volume for domain, rather than the much higher value for domain with content.
Nevertheless overall a positive state of the domain world!
Bob