Steven has vouched for him, as such his credentials are beyond reproach.
Not to mention the "inside sources" have been correct as far as we can tell. We do this at work all the time, plan for this date, oh crap not ready let's push to this date and re-evaluate as we get closer.
As hundreds have said, there is no way of knowing when we will get the phone. There can be thousands of leaks indicating when the next planned release date is, but if they can't finish whatever they are working on in time then they have to push back to a new date.
All of these rumored dates (at least in terms of 9th and 15th) are almost assuredly planned dates and the only people who know if they will stick to this date are the people that are testing whatever issue they are having and the top execs.
Best Buy, Radio Shack, and the majority of local VZW reps rarely even know the planned release date let alone how the testing is coming.
To those saying "my radio shack rep said still come in on the 15th," these are the sources that were the most wrong. Just like last time, your reps that say still come in this day will either call to cancel or cancel when you arrive. These reps simply have not received the cancellation of the planned release dates (that they may or may not have received in the first place).
There are very common themes here that people (including myself) are desperately trying to ignore.
TL;DR: Rumors are of planned release dates only; they give no indication of whether product will be ready for this date. Local reps are more in the dark than AF is so appointments are no indicator.