The Semantic Web needs a MySQL
One thing was clear in the comments of many industry-facing participants of ISWC 2010: a big impediment to adoption of semantic web technologies is the lack of an off-the-shelf triplestore that "just works."
There are many other problems, of course: RDF an awkward format when it comes to real world programming because the graph model doesn't align to the object-dictionary model of OO programming; JavaScript favors JSON instead of RDF; URIs and namespaces can be a burden to craft the first time around. But these problems can be lessened, or eradicated, with good development frameworks.
Underlying these surface problems is a deployment one: even if a company wanted to, there's no clear hassle-free solution to getting a triplestore up and running with the same ease, access, and reliability that relational solutions such as MySQL and Postgres provide. And as long as this is the case, otherwise semantic-web savvy individuals are going to continue to live in the relational world. When people are spread thin, and want to focus on user experience instead of database administration, they'll pick the database product that allows them to focus on other things.
So what gives? Do we wait for a Mike Stonebraker of the triplestore world to come around? Or do we try to bolt our technologies onto non-relational databases with gaining momentum such as MongoDB or CouchDB?