The extra $200 is from Panasonic - a total of $400 in mail-in rebates.
When I talked to the sales rep, Candace I asked how long, and she said they had just gotten this from Panasonic today and did not know how long it would last (although it sounded like they update or renew these deals on a monthly basis).
Its a fantastic deal, especially considering the 700u only went for this amount at the very end of their cycle.
In addition, Audioholics members get a $150 free upgrade warranty that extends the standard 1-year to a 2-year warranty.
Add to that the $300 in blockbuster cards and you're geting $850 in freebies. That's astounding.
~Josh