So I thought I'd post it here, see if anyone else could figure it out and it looks like a few people have good suggestions - gotta love HN.
http://www.google.com/trends?q=newgrounds,+reddit,+paul+grah...
"Originally, Google neglected updating Google Trends on a regular basis. In March 2007, internet bloggers noticed that Google had not added new data since November 2006, and Trends was updated within a week. Google did not update Trends from March until July 30, and only after it was blogged about, again.[2] Google now claims to be "updating the information provided by Google Trends daily; Hot Trends is updated hourly."
Google Insights for Search seems to be better for this sort of analysis since it offers regional filtering options and puts the searched term into context.
http://www.google.com/insights/search/#q=xkcd%2Cpenny%20arca...
Similarly there's no spike if you look at just the US or just the UK.
Perhaps Baidu was down or something but it seems most likely an error on just the compiled graph.