Yahoo is apparently ready to make its biggest acquisition since CEO Marissa Mayer started running the company in July 2012. AllThingsD.com reports that Yahoo's board of directors has indeed approved its rumored acquisition of the Tumblr blogging service for the massive price of $1.1 billion.

The report comes just ahead of a previously announced Monday press conference the company plans to host, where Yahoo has only said it plans to announce "something special." While some reports claims Yahoo was going to reveal something related to its Flickr photo sharing service, it's possible that its purchase of Tumblr will come up as well. AllThingsD also reports that Yahoo was the only bidder for Tumblr despite rumors that Facebook and even Microsoft were planning to put an offer for Tumblr on the table.

Yahoo would certainly like to increase its audience with a younger generation, and bringing in Tumblr to its network of sites would do that nicely. The service, which launched in 2007, now has about 108 million blogs and 100 million unique monthly visitors every month. Tumblr is extremely popular in younger demographics, an area where Yahoo has struggled.