New Mobile Ads Coming to Tumblr (3)
Tumblr has gained massive momentum over the last few years, could be a great traffic opportunity to jump in and test the waters when it launches. 
http://mashable.com/2013/03/05/tumblr-mobile-ads/
I was just reading about this a few minutes ago.
Personally, I can't wait to test their traffic out 
Interesting, looks like a lot of traffic and it'll be nice fresh social traffic
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