I like how reactionary that is, much like when people expected Instagram to suddenly gain pokes and sidebar ads when Facebook bought them. It may as well say 'WE DON'T LIKE CHANGE'.
It's funny how when there's news of a company acquiring another people think straight away that it'll change drastically and overnight, making the huge assumption that the company is A) going to change anything B) doesn't know that changing something will break trust with users making their billion dollar purchase useless.
Or maybe Yahoo will change things on tumblr who knows? I'd like Yahoo to add a feature to change your primary blog on tumblr. That would be nice to have..