It allows for multiple windows, which is somewhat similar.
With the iphone's touch interface this is painless and I can't imagine it'll be any worse for the ipad.
His example of having (AT LEAST) 8 tabs open is not the same as eight windows. Searching through all of them can be quite the inconvenience. I, for example, currently have 14 tabs open, and six applications running. I do not want to search through all of those to get to what should be "another tab." I understand what he's talking about...