I am posting this entry from the PowerBook: it's back. After being pretty impressed with the customer service back on Day 5, I figured that while the next-day delivery estimate was probably optimistic, the part certainly should have arrived by yesterday, and I really should have heard something before today. So at 9.00am this morning, I called. There was a minimum of fuss: the PowerBook was ready, and, in fact, had been ready yesterday. The person I spoke to apologised that no one called me yesterday, and was surprised I didn't receive an email telling me so.
I picked up the PowerBook. It works. The "top case" was replaced, and that cost $A 309.09 ex-GST, with just under $A 70 of labour. Interestingly, the original $A 75 I paid at drop-off time was deducted from the total, and I left paying less than I was expecting. I didn't stop to ask too many questions.