Magpul has a PDF on their website suggesting they will offer the PDR for sale to everyone (civilians too) in 2008. I like Magpul products a lot. They generally do things well and think the design through very thoroughly.
In some cases, they have dropped product lines because they were able to introduce an improved product that made the old one obsolete. For example, the M93 stock was originally slated to have a bunch of accessories but instead of developing the line of accessories Magpul redesigned the stock to introduce the UBR. M93 owners will be given a chance to buy the UBR at a discount; but not all of them are happy about the stock being discontinued.
In other cases, they have given estimated dates that they did not meet. As a result, they no longer comment on dates and any dates you do hear should be considered guesses at best.
If they do release the PDR in 2008, I definitely have a space open for another SBR.