Im a web/graphic designer aswell, YOU DO NOT need a Mac Pro, its a waste of money, I would recommend you get an iMac, remember that Photoshop & Illustrator are memory intensive, doesn't really require an amazing processor. I would get 4GB memory. That should do you well, if you do a lot of 3d renders then you might want to get a PC imo with Quad Core..
My thoughts.. Im actually getting an iMac for the same reason, but I only mostly use photoshop & dreamweaver.
Anyway if your eMac has been doing well for you then imo the iMac should be more then enough.