BlackBerry PlayBook headed for a fire sale?

It certainly looks that way, as the 7-inch tablet’s retail prices are plummeting. The PlayBook, which debuted at $499 for a 16GB model, now costs just $299 at Staples, after a $100 rebate on a Visa prepaid card. Best Buy and Office Depot are offering similar deals, except they’re giving away store gift cards, instead of a prepaid card that can be spent anywhere. Meanwhile, Walmart is ringing up the 16 GB Playbook for $250 in various locations around the U.S.