The battery in my MacBook Pro was on its way out. (It had developed two interesting (and by "interesting", I mean "highly annoying") behaviours. Firstly, it could barely hold a charge, even when the machine was asleep—it would drop from 100% to 50% in three days of sleep mode. Secondly, it no longer allowed the machine to shut down gracefully. Instead of the orderly warning icon and dialog at low charge, the machine would just spontaneously shut down. And not just at 20% or 10% charge, but at some random point which could be as high as 50%.) So I ordered a new one.
Shipping took longer than I had hoped. I've become accustomed to pretty rapid order fulfilment with Apple, but this took five business days to arrive. The packaging is nice. The battery arrived showing two (of five) LEDs on the bottom surface, and claiming 50% charge once I booted the machine. It seems to be charging. Overall, seems like a great battery. Of course, it's also the only battery available for this machine. And it wasn't cheap at $A 199.