Of 11 people he surveyed for his blog, I would judge that five had a positive experience submitting their app to the App Store, four were neutral, and two had a negative experience. The SDK received similar reviews, with six developers regarding it favorably, four were neutral, and one developer regarding it unfavorably.
Two of the developers with positive experiences said they submitted their app before the App Store was launched, and it was approved for distribution in about a week. The two developers with negative experiences submitting their app said that the most frustrating parts were waiting and the lack of communication.
The positive, neutral, and negative ratings were not a part of his interview, but were indicative of the general tone that I could determine reading the interviews. They are subjective on my part, and opinions, of course, may vary.
The interviews are interesting reading if you're considering developing an iPhone app.