Was waiting for new iMacs but now should I just buy a refurbished? Is the only thing that they are thinner (no difference what so ever to me-its a desktop mine is fine at mo), and faster? I currently have a 2007 alu iMac, 2GHz, 4Gb RAM. I use it for general computing, surfing, iTunes, iPhoto, little bit of iMovie. I was hoping for a little more and I'm more inclined if I do buy another iMac, I may as well buy last gen?