Tech guru and pundit Tim O'Reilly, an early fan of Google's OpenSocial platform, has changed his tune. In a recent blog post titled "OpenSocial: It's the data, stupid," O'Reilly blasted Google for failing to adhere to web 2.0 principles in creating the new platform.

According to O'Reilly, OpenSocial is a big win for developers because it allows them to more easily port applications across the web. Catering to developers alone won't help users extract value from OpenSocial, O'Reilly said.

"We want applications that can use data from multiple social networks," O'Reilly wrote. "And data mobility is a key to that. Syndication and mashups have been key elements of Web 2.0 -- the ability to take data from one place, and re-use it in another. Heck, even Google's core business depends on that ability -- they take data from every site on the web (except those that ask them not to via robots.txt) and give it new utility by aggregating, indexing and ranking it."

At the Web 2.0 Expo in Berlin, Patrick Chanezon, Google's developer advocate for OpenSocial, explained to the crowd that data portability was not part of the program.

Google launched OpenSocial and quickly enlisted the support of MySpace and other social networks in a bid to counter the growing threat from Facebook and Microsoft. However, as Mark Cuban pointed out, few users will have a need to switch to Google's OpenSocial if Facebook continues to open up its platform.