Dave Burke mentioned on CS Daily News last Monday that both MSDN Blogs and TechNet Blogs have been updated to Community Server 2.1. However, in my opinion they missed to make use of one of CS's most interesting new features: tag support.
I used to have MSDN Blogs' mainfeed in my aggregator, but deleted the subscription almost one year ago. There are just too many bloggers, and the signal-to-noise ratio is somewhat low. Therefore, instead of subscribing the main feed I'd rather subscribe to specific global tags, e.g. CLR or WPF.
Fortunately, it's already there. You may have noticed in the previous paragraph that both CLR and WPF are hyperlinks. So tags are there, it's just that they are not first-class citizens. In fact, the links to the sites' tag clouds are http://blogs.msdn.com/tags/ and http://blogs.technet.com/tags/. So I ask, "Why aren't these links on the sites' home pages?"
(However, of course the global tagging system works only if all bloggers commit to a common set of terms. If one tags his posts with WPF, another one Windows Presentation Foundation, and a third one uses Avalon, you would have to subscribe to all three of these terms.)