Appropriately enough this started in Boston with an event called NoSQL Live that was completely sold out.
Projects like MongoDB, Apache's CouchDB, and Apache Cassandra all presented their stuff at NoSQL Live. Major database users like Twitter, Digg, SourceForge, and GitHub all say they're on board with the idea. Hundreds attended the live webcast.
It gets more serious Monday, as 10gen announces a services and support business model built around MongoDB. This is primarily a Silicon Alley shop, with co-founders Dwight Merriman (DoubleClick), Eliot Horowitz, (ShopWiki), and Kevin Ryan (AlleyCorp). The roll-out includes a MongoDB Day tomorrow and an event in San Francisco on Tuesday.
Maybe we shouldn't bring up science and natural forces at a tea party (sentence first, trial later), but all this does strike me as a natural reaction. Fear of lock-in, not just by vendors but by technologies like SQL, is built into the open source movement's DNA. It's a good thing.