Shifts in the blogging��tide Which semi-open platform do I like��better? I���m reading ���How Yahoo derailed Tumblr,��� an excellent story by Seth Fiegerman over on Mashable, and it���s making me think of my own relationship���������such as it is���������with Tumblr. I have more than one friend who thinks of Tumblr as the domain of endless streaming GIFs and disaffected armchair activists looking for things to be angry about.