No Market Share movement for WordPress 2.5 yet sorry.
Get a list of 18,345 websites using WordPress 2.5 which includes location information, hosting data, contact details, 5,215 currently live websites
which includes 704 domains that redirect to sites in the list. 13,834 sites that used this technology previously and 1,043 websites in the United States currently using WordPress 2.5.
Distribution of locations of all WordPress 2.5 customers we've ever tracked.