Those of you with MacBooks and MacBook Pros purchased between Feb '06 and April '07 should grab this update. There's some problem with these notebooks that occasionally makes it so that your battery won't charge, won't recognize, or reports a low charge when it's fully charged and has a battery cycle count of less than 300. Oh, and those deformed MacBook Pro batteries? That's caused by this too.
If you install this update and your battery's still acting up (showing the above symptoms), you can head into an Apple store and get a free battery replacement. Especially if you've got that 300 cycle count thing. Because that's madness.
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