rogerd - 4:25 pm on Feb 22, 2012 (gmt 0)
More zombie discussion here:
Glad you found a solution, Arkanoid1984. This seems to be a botnet of infected Windows machines, which would explain the diverse IPs, UAs, screen resolutions, etc.
Other sites experiencing this seem to be Wordpress sites as well, but the sample size is too small to say whether it's coincidence or WP sites are being targeted. Not really clear what's going on, the volume on one site I watch isn't high enough to be a DDOS attack (it's been as high as 30K pageviews in a day, but the site can handle the load), nor does the site seem like a logical DDOS target.