Apple has often (in recent years) been in a position where significant portions of their revenue are from product categories which did not exist 2 years ago. There is a fear that they will not continue to invent/expand into new categories.
So personally I'd list the new product categories as only two - the iPod and iOS. It's just that iOS' revolutionary impact hasn't completely played out yet. I expect any new 'product categories' to be further extensions of the iOS family into new markets. e.g. Apple TV is an existing product running iOS, but if it grows an app store and games ecosystem, will that make it an entry into a new category?
You're right that the Mac Pro is an existing product line, but it's so radically different from it's predecessors that I do think it has a chance of being used in ways and contexts the old Pro never was. For starters it's tiny. It's agressive use of Thunderbolt is interesting, but also the emphasis on GPU utilisation via CUDA and OpenCL - one of it's GPUs isn't even wired up to be used to drive displays - is a bold move.
These are incremental, not reinventing. These are successes, but they shouldn't be held up as reinventing when they aren't.
...Well at least it's not as bad as the XView cmdtool.
Plus this whole inventing new categories things is silly, you'd have to go back a long way for Apple to have created a category, they excel at being more refined than existing players.