Ishbar -- all that information is available in the FAQ, but the lowdown is this:

The titles (ie junior member, senior member, etc) are only reflective of the number of posts that person has.

The AntiPoints you have (little light and dark green dots under your name) are (ideally) reflective of the quality of your posts. If you start posting inflammatory remarks, you'll see those little green dots turn red and with enough reds you will eventually you'll be banned.

Finally, the "user tends to assign" bar is indicative on how you rate your fellow AO'ers. If you tend to rate high, your arrow will be in the green, if you rate negatively your arrow will be in the red.

The FAQ has more information.

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d'oh! beat me to it!
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