&channel= in stats from google

[UKSBD]

Anyone know what &channel=linkdoctor is?
Just found it in my stats like this,

"google.co.uk/search?q=KEYWORD&channel=linkdoctor"

[nickjohnston]

That is intriguing. I can only find one brief mention on the net, and doesn't give any details.

http://acuteaccent.com/operator-channel-linkdoctor-on-the-path-of-google-urls/