Excellent post from Stephanie Booth about being realistic about what blogging can bring you:

• blogging is a long-term strategy: it will take many months or even years for you to see what benefits it’s actually bringing you
• don’t obsess on visitors and comments; instead, focus on what is said about your blog, and the opportunities it brings, in terms of contacts, open doors, favorable dispositions (qualitative measurement rather than quantitative)

I’ve nicked the handy summary above, but it’s worth reading the whole thing.