It seems that Apple is aware of a problem with some early MacBook Pro batteries, and is cross-shipping fresh replacements to customers experiencing specific issues. The problems are not widespread and seem to be restricted to MacBook Pro models with serial numbers up to W8608, meaning that only the machines produced in the first two weeks can be affected.

Symptoms of the faulty batteries include battery power level going from a full charge to 90 percent, then immediately off, the battery often either going directly to one blinking LED, or failing to respond at all, and some users may experience a sizeable loss of battery capacity.

Jason D. O'grady explains "how to decode your Mac's serial number: The first two digits are the FactoryID, the third is the year of manufacture and the fourth and fifth digits are the week of manufacture. A serial number starting with W8607 means that the unit was manufactured in facility W8 (Shanghai China) on the 7th week of 2006."

This latest chapter in the saga of the MacBook Pro issues seems to be a lot less common than the others, and a quick check across Apple forums reveals that while there are a few oddities regarding the batteries, the problems described above are not widespread.