Floof-O-Meter is basically a karma system.
Once you reach 25 posts you can "Nuzzle" people if you think their answer is good or if they've generally done something good on the forum.
Earlier, there was a way to take away points, which was to "bite" people.
You can't change your in-game username. Only the name on the forum.
To do that, you go onto "Profile" and select "Account related settings."
Hope this cleared things up.
Tata.~
(http://i1299.photobucket.com/albums/ag69/Youshallfearme2/3958a2d7-d085-4418-bf84-ed99811f02d9_zps2e50240c.jpg)
The Floof-O-Meter is one way to thank someone who has helped ya around here on the forums. You give them a floof with the nuzzle button seen above.
Also, just to add onto what everyone says. You might want to pick a username(for the forums) that really isn't to common. The name Amber I've seen way to many times and usually your PMs will not get to you cause of such a common username.