Well, I finally upgraded my laptop to Lion the other night, and what I adapted to fairly quickly on the mouse scrollball has taken a whole lot of getting used to all over again on the laptop trackpad. Pushing my fingers up to push the content of a web page up is actually fairly straightforward, and I guess I've adapted to that already. What's really driving me nuts is scrolling around photos I'm editing. I guess that's in a different mental pigeonhole than scrolling around web pages, so my brain isn't picking it up.
I know I can turn it off, or switch back to the old behavior, but I'm refraining from doing so. I know I'll adapt eventually, again. In fact, at last June's Worldwide Developer Conference, the Lion developers made a point of calling our attention to the change, and saying that while there's a preference checkbox to restore it to what we were familiar with, they urged us to give it a week or two and promised we'd get the hang of it. It does feel pretty natural, and makes sense in the context of the similarity to the iPad behavior. The big difference is that on the iPhone or iPad, you're pushing directly on the content with your finger, and on the Mac, you're using a displaced control device, whether it's the mouse or the trackpad. Steve Jobs actually spoke once about the idea of a touch-screen Mac interface, and said it's just not natural to reach out to the Mac's screen the way it is to touch a phone or tablet screen.