Why law students should start a blog.
The link above is aimed at law students thinking about solo practice, but it's still relevant. Also, I should add that when I was interviewing for my firm, I heard through the grapevine that a partner expressed pleasure upon hearing that I had a law blog! Granted, my firm is an IP boutique in Silicon Valley with (probably) less fearful views of the internet, but still.
So go for it.