Latest Obsession

Currently living day-to-day by the posts of mac rumors.  They have a great buyers guide, which tells you (based on history) if you should buy the product now or if its near the end of its cycle and may be upgraded soon.  Problem is I have been wanting the iPhone and when I last looked it was on ‘buy only if you really need it’ and when I looked again its changed status to ‘dont buy, upgrade soon’.  How long must I wait????