According to Digital Bits (and they are correct over there 99.9 percent of the time) the adverytising was just wrong and all the discs are the documentary. They simply misprinted it. Here is the whole passage from digital bits. It also includes some information about the deleted scenes controversy.
Finally today, a lot of you have been wondering what's up with Fox's X-Men: The Last Stand DVD. Some readers have reported that select copies of the DVD were released with 22 deleted scenes, while others have only 10. We've checked with our industry sources and have learned this is true. However, we've also learned that the number of discs that were released with the larger number of deleted scenes is very, very small - so little in fact that they all sold out early on the first day. We don't know why they were pulled, and speculation runs from a problem with clearance issues on the deleted material to the possibility of Fox releasing an even more elaborate special edition in 2007. Either way, there was no way to tell which disc you were getting based on the packaging. The main thing to know, is that if you've already purchased a copy and have been thinking of returning it hoping to get one of the copies with 22 deleted scenes, don't bother. Those discs are LONG gone at your local retailer. In fact, if you purchased your DVD on the first day but haven't opened it yet, that's your best bet short of eBay for getting the version with more deleted scenes. Also, as far as Wal-Mart's bonus disc - the packaging claims the bonus disc inside will include a pair of making-of featurettes, and then when you open it, you get a featurette on the history of the X-Men comic book. The packaging was simply mislabeled. You're getting exactly what you're supposed to be getting. We hope this information at least helps ease your minds a bit.
