77% iPhone owners will buy again.

According to an article on CNNMoney, iPhone 4 has strong customer loyalty.  This is based on a survey by the Yankee Group.

To quote the article, "...The iPhone is also the gift that keeps on giving: 77% of iPhone owners say they'll buy another iPhone, compared to 20% of Android customers who say they'll buy another Android phone.."

This is still early days.  I am not sure about the survey's sample size.  To be fair to Android, earlier versions are not as impressive as the latest Android 2.2 Froyo.  Customer loyalty might change in the future.

Either way, having Android around means the iPhone will innovate faster to keep up with  competition.  This can only be good for iPhone owners.