On the 12th of March, 2012, I tweeted a link of an old video we made. It went on to get 164 retweets and April 2nd I tweeted about a Skyrim Video hitting 1.5 million views it went on to get 163 which I would have never known!
For the hell of it I took a look at Mashable and TechCrunch as I look at the sites every day.
Mashable tweets 75 tweets/day on average with links to the latest articles on mashable.com. Analyzed the past 3200 tweets from them to discover the most retweeted tweet. Two months ago, on December 5th 2011, Mashable posted this and it got 2,297 re tweets.