Agreed. My PowerBook has not proved to be at all as durable as a "pro" product should be. I am seriously considering a MacBook for my next computer even though I hate the glossy display and the awful new keyboard, because I am loath to spend $2000 on a MacBook Pro that I know is not going to hold up very well to the kind of unrelenting heavy use I give it.if they return to plastic, I would not mind. Aluminum is sexy and all but it dents easily. I want a notebook that's durable enough so I don't need to baby it all the time.
If they must use metal they should use magnesium alloy or even titanium (wait, didn't they use that once ?) which are a lot stronger than aluminum. I think the Lenovo ThinkPads, at least the higher-end ones, are magnesium alloy.