As a means to encourage new users to look at tag wiki and become aware of them, I suggest that we add a new bronze badge for reading
x different entries of tag wiki (which has some content), where
x can be from 1 to 5.
I personally prefer the number to be 5, so as to increase their chance of running into some good content (well, not all tag wiki are good anyway). When they have found out the usefulness of tag wiki, hopefully, they will check them out later.