I'm surprised. Has Apple delayed due to bugs before?
http://www.iphonehacks.com/2010/11/developer-reports-major-v...
Source: I found/reported the bug mentioned in the article.
"A year later, this was amended to Spring 2007, however on April 12, 2007, Apple issued a statement that its release would be delayed until October 2007 because of the development of the iPhone."