Hi, I would like to invest in a new apple computer, most of my work is in video editing. I was looking to invest in a mac pro but I am a little worried that if I invest let's see $4,000 and Apple in a couple of year put a new computer on the market I would be stuck with an old computer. It's there anyway to know when Apple is going to put a new computer in the market? for example a G6?. Thanks.