I have already wondered this question for myself. I made a decision in one blog to take notes both on professional topics and personal ones, for my life.
Although over time I began to realize that, on the one hand, a high-quality thematic blog maintained by an expert gains authority over its field over time, on the other hand, sometimes I want to write something from the “watched movies” series or “go for a walk” That would stand out from a serious expert-style blog.
How to be? Start another blog, LJ? Or is there such a facet of popularity that you need to go and after which even your note “I bought a disc” will be read, commented and it will be waited?