I've got several thousand requests for this in my logs with an IP address in the same /24.

Two weeks ago it was using a different user agent:

    Mozilla/5.0 (iPhone; CPU iPhone OS 6_0 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/6.0 Mobile/10A5376e Safari/8536.25 (compatible; Fetcher/0.1)

This string is mostly from a beta build of iOS 6.0 beta 4, but with the same suffix the author discovered.