In the earnings call yesterday Apple's CEO Tim Cook made statements that could mean that Apple is not announcing anything new until fall.
Apple released its Q2 Earnings yesterday. In the conference call after the release Tim Cook said some things about Apple's product release schedule. According to Apple Insider, Tim Cook said that there will be product surprises coming in the fall and 2014.
Does this mean that Apple will not release anything new until fall? No spring or summer announcements? It could well be and as I sad before iOS 7 could be to blame.
As iPhone sales are solid there is also no reason for Apple to get nervous and jump the gun on a new iPhone release before fall. The iPad is also selling great. Only Mac and iPod have issues, but that is not necessarily a product issue.