Two years ago, Opera claimed that they submitted an iPhone browser to the App Store only to have it rejected, a claim that was later refuted. In a comment posted to the Opera blog earlier today, Espen André Øverdahl, the Community Manager at Opera Software, said "We have not submitted it yet to the Apple App Store. However, we hope that Apple will not deny their users a choice in Web browsing experience."
Before you assume that Apple will deny an iPhone browser because of Mobile Safari, note that there are several other web browsers in the App Store already, including Perfect Browser 3, Full Browser and Mercury Web Browser. As John Gruber notes, however, the browsers that are in the store use the system version of WebKit.
[Via Daring Fireball]