I am two months old on hubpages, and have written only 19 hubs so far. I actually do a lot of research about the topic before I write, they are usually topics of my interest and a little more deeper understanding gives me my flow while writing.
I choose topics of general interest, from current affairs or from my teaching experiences.
I am a member of hubmob weekly, so I try to make at least one or two hubs on the hubmob topic every week - that gives me hubmob viewership and followers.
Actually right now in the next three months I am planning to experiment and write on as diverse topics as possible to get a good collection of hubs. Then I'll analyse, which topics do well and attract readers and which topics aren't very important for others.