I'm sure there are plenty of vulns in Windows XP by now, but it seems surprising to me that a random IP is getting scanned + infected + exploited within such a span of minutes just because it's running an old OS.
It would actually be pretty interesting to see which vulnerabilities are used for this type of thing. Sort of the opposite of a 0 day, I suppose... very old, well known exploits. But to do that on a PC with totally stock OS software is impressive.