Those points show how active and helpful you are on italki community.

I've noticed they give 30 points for each correction you make to a notebook entry,

and 10 points to write a comment. I'm not sure how many points they add for

answering a question :')

I've been a member here for nearly a month (short of two days) and hang around the Notebook and Discussion boards for fun, for a while. I have one friend listed, haven't taken any classes or written any notebook entries myself, nor started any discussions. Before answering this entry I had 2950 points.

Edited: Now I have 2960 points, by answering your question, so my little experiment shows it's 10 points per answer, it would seem. The quality of the answer is not measured, however. ;-)