The idea of blogging being like a curator’s job fits for blogs that have a central authority figure who plans out posts for future days. Content, style, and timing all figure into this idea. Most sucessful blogs seem to have a curatory approach to how they are constructed. Curating seems more techincal than blogging, and thus could discredit the idea that posts are strategically constructed and attached to the blog. Blogging is a more laid back approach to presenting a given topic, while curating requires more work.
I think just about any individual can be considered a curator if they blog. For group blogs, that idea may only be slightly true, individuals posting about whatever they want, without having someone decide what the blog or a specific blog will be about. I think Grantland.com serves as a good example, as posts are strategically about sports during a particular month/season and pop culture to reflect current and upcoming television, movies and music.