Jimmy Gilberti doesn't like it, and neither do I. Maybe we're missing something. On his Quimondo website today he rails about iTunes 9, which he says gives inferior App Store search results compared to the old version. The reason: you can no longer sort by popularity. Do a search on a generic term such as "horoscope," and the search results appear in seeming random order. Lots of pretty icons but no information about the apps relative to the others.
Also you might be interested in the iPhone metrics he's posted on his site. He puts together some pretty interesting stats about the iPhone. His analyses include, for example, charting the growth of unique apps and the linear growth in the number of developers. He's also charted the 10 most updated apps and the percentage of iPhone apps with updates.