This is a battery exchange program for “certain rechargeable batteries that were sold for use with 15-inch MacBook Pro computer systems from February 2006 through May 2006”. The Apple page linked above says this is NOT a safety issue ... they’re being recalled because they “do not meet [Apple’s] high standards for battery performance”.
This is most likely a proactive move on Apple's part. Some bloggers have linked Dell batteries and Apple batteries together.
I just wonder how much this will end up costing Sony - the manufacturer of the batteries for Dell and Apple. I wonder if this particular recall is costing Apple anything.
This will be added to The Fix Your Thinking reference section:
Apple & Apple Related Safety Warnings & Recalls