Direct questions hover around 1/1. Questions sent to followers, 5/1. It’s probably a higher engagement, albeit different, than Tumblr/Twitter/FB.
When you ask a question on Twitter, how many of your followers respond? Very few. The nature of both sites is obviously different, but the engagement on Formspring remains pretty good.
Also, there’s only so many times you can answer a question about your favorite movie, or where you met your husband/wife before it gets boring. Original questions (with photos, links, tags) get a far higher response rate.
You really think 5/1 is bad?