Generally, I think the best way to sum it up is interested indifference.
I don't expect the majority of commercial software that I use will make it to the app store.
I do expect a lot of small apps/utils/games to pop up from smaller devs. A lot of IOS-like stuff popping up, and some of the existing small app/util market may move over, too.
While I have a lot of that stuff on my iPhone, that's not what I personally use a Mac for. I do heavy-weight apps and some email and occasional surfing. Beyond that, I'm not even at my computer.
If I'm looking to buy something, though, I might buy it from the app store if there's a value-add (for example, better licensing or cheaper cost).