I'm glad I came across your blog today ! I just switched abruptly from photography to audio recording topics after moving and having our studio renovated, so I was kinda worried I might've lost some readers or photo-viewers. But you're right by saying sticking to a single topic or niche can be boring. I guess transitioning gradually or coming back to a previous genre/topic every now and then is better.
RE: The Q Everyone is Asking-- How Do I Get People to Actually Read My Blog?