The long-awaited Specialist badges are now working; you can browse them on the badges page.
After I worked with it for a while, I realized that these are just tag-based badges, so I dropped the "Specialist" name and stuck with the name of the tag as the badge name.
There are two levels:
Silver 400 upvotes Gold 1000 upvotes
... for non-community-wiki answers on questions with the specified tag.
I was originally going to include community wiki answers in the calculations, as badges have historically ignored that designation. I changed my mind, however, when I saw the huge number of silver and gold "subjective", "fun", "off-topic", etc etc badges this would create. :)