This shouldn't reflect poorly on Apple's bottom line although it will cost them a lot of money I'm sure. The big loser is going to be Sony who contracted to manufacture the batteries for Dell, HP, Sony, and Apple laptops.
There's a good video on CNN explaining the problem and how to find the serial number. (Not linkable)
Affected models include:
• 12-inch iBook G4 A1061 ZZ338 - ZZ427 / 3K429 - 3K611 / 6C519 - 6C552
• 12-inch PowerBook G4 A1079 ZZ411 - ZZ427 / 3K428 - 3K611
• 15-inch PowerBook G4 A1078 and A1148 3K425 - 3K601 / 6N530 - 6N551 / 6N601
These are the serial number ranges (revised by Apple this evening) If your model falls within these ranges you can get a free replacement.
Remove your battery and look at the serial number.
Now that some 6 million Sony-manufactured batteries have been recalled, and all the big names are preparing for a summit on standardizing manufacturing processes for li-ion cells, we were just waiting for the fingers to start a pointin'. Well, a pointin' they have begun, as Japan's trade ministry ordered Sony (with Dell) to investigate the issues surrounding how a few million batteries were manufactured in such a way that a percentage of them might just explode all crazy on their owners. The Japanese trade ministry ain't screwing around, either -- Sony and Dell are to report back their findings, or face severe penalties under Japan's consumer safety laws.
* Edit note: If some of you happened to catch this post during the "editting phase" I listed 1.1 million batteries recalled ... this is because 1.1 million are USA and 700,000 International.
If you have a 14" iBook or a 17" PowerBook G4 you are not affected by this recall ... the majority of these batteries were made by LG (not Sony) ... however, please pay close attention to this site for any alerts on these models.