Congratulations to John Welch and his TTABlog. The TTAB (incorrectly in my mind) determined that TTABlog is not an inherently distinctive mark, but determined that the TTABlog has acquired enough distinctiveness to be registered on the Principal Register under Section 2(f). Post here.
Just a note about the TTABlog – not only is it distinctive (whether inherently or acquired), but it is probably the best source of TTAB case law that you can find. Move over, McCarthy!