We were discussing this on my other board and it is just an issue with battery quality.
"This is an example of that happens when the barriers inside a Lithium-Ion battery are faulty, it causes internal shorts --- which then melts the barriers more --- causing more metal - to metal contact (in the battery), causing the whole thing to go up in flames from the heat of the short and "pop" from expanding gasses."
Dell has battery recalls all the time, but always on only one specific (faulty) model of battery. Other companies do this too, but Dell seems to be the only ones that catch on fire or explode. The Mac batteries just get a little puffy and quit working.
My favorite about this story is all the guys standing around in the conference room watching a lithium ion battery burn and billow smoke. HELLO, SUPER TOXIC GAS! Don't breathe that you idiots!
EDIT: KenM, all Dell systems' user guides are available online via their website. The excuse was that users would always have the most current version of the book, but it was really to save money on printing/shipping.