The Wikimedia blog is still on WordPress 2.5. I moved three blogs on my own site — this one, Cyber Chatelaine and Rocknerd — to 2.6 today. The first two were fine because they were all but unmodified from the standard install; the first has lotsa tweaks and extensions, and I had a marvellously annoying time this afternoon fixing it up and I’m still not finished. Grah. I have recommended severe beta testing for the Wikimedia blog before updating.