I think the difference in this case is that unlike Flickr, you can do a whole lot more on/with Tumblr. It isn't just a photoblogging site, you can interact with the members in different ways to that travesty known as Flickr. Also, I think Marissa Mayer knows about the skepticism surrounding this recent acquisition and is likely to strive harder than any person in her position has done before. I'm a bit worried about the 'family friendly' policies that Yahoo has adopted, however. If they try to implement family friendly policies on Tumblr then the site will be destroyed in about a week.
- GLaDOS (Portal, 2007)