Oh no! :) Yes, I use all lowercase on Twitter and Eksi Sozluk mostly. I don't write in all lowercase on Reddit, HN, or Quora, or forums, etc where different type of capitalizations mix up. I find non-uniformity less pleasing to the eye than proper capitalization.
I also write my emails with proper capitalization too, for similar reasons.
I also write my emails with proper capitalization too, for similar reasons.