Hopefully this will make it easier to find apps, because it's certainly not easy now. The categories are so vast and each one so densely packed (there are 65,000+ apps in the store as of this writing), that finding the one app that will do what I want is a chore.
Keywording is a small step, but as Tim Cook noted in last week's earnings conference call, there is plenty of room for "further improvement" in app listings and search/accessibility for finding the apps you want.
Since the store's purpose is to drive iPhone sales (from Apple's perspective), we're sure they're motivated to get it right.
Update: At least one developer is reporting an issue with the new service.