Great summary of Tumblarity and the issues a lot of people have with it by chartier:
Tumblr could quell much of the uproar over Tumblarity and the new Directory by simply allowing users to disable them. If you don’t want to see your Tumblarity displayed in the Dashboard, the option could remove that number altogether. Perhaps it could even remove those numbers from the Directory listings, or just remove the Directory link entirely.
Further, with no effort on the part of Tumblr’s staff, users could also opt to just not care about Tumblarity if it isn’t their cup of tea. I’m mildly interested in the system, largely in part because I wish there was more context behind what the Tumblarity number means. But just like I didn’t care about the petty people who tried to turn high school into a popularity contest, I’m not allowing this new system to negatively affect affect what, when, or how often I post. Like television, the Tumblr Directory is a useful tool that can be harnessed for good (discovering new interestingness) or bad.
We can chose to care about Tumblarity number and allow it to affect our blogging, or we can chose not to. I don’t see what the big deal is.