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Tumblr's business model revealed to be "good feelings." Sounds like someone's been reading Lovemarks. (You remember: "Take a brand away and people will find a replacement. Take a Lovemark away and people will protest its absence.")
Tumblr: Everyone gets a trophy.
TL;DR
Ah, now that explains why we won't ever get on the radar.
Those hearts are addictive little uppers.