I want to know what add-on this guy is using! If anyone knows please tell me! Thanks!

Here is the link to the pic!

http://i.thottbot.com/ss/o/38519.jpg

Exactly what addon are you asking for? There are quite alot of them on that pic.

in the bottom left corner the action bar looks like an arch...thats so neat! thats the main one i want to know

I am afraid I cant help you with that one. :/

I would say it's Bartender3 and cycircled but i'm not sure but in my oppinion the actionbar looks ugly ;X

It's cycircled alright. However, I believe he's using trinity bars as I know trinity allows for oddball shapes when doing action bars.