In keeping with the theme of Dragon Ball, users won't have their # of posts shown to the left of their posts; instead it displays their power level.
The power level system works in a similar fashion to a post number system. Where they differ is that, while posts keep track of only the number of posts, your power level is based on how much you contribute to the forums through your posts. Your power level will increase when you post helpful information that other users may then thank you for. You may also thank other users for posts that you found helpful or entertaining, which will in turn increase their power level. To do this, click on the "Thank You" button:
Located beneath that user's post. The amount that user's power level will then increase depends primarily on your own power level, and there are limits as to how many times you may thank the same user, or thank any number of users in a single day.
Anyone caught begging for power level increases or abusing the power level system will have their own power levels reset and may be prevented from ever being able to increase their power level again.