I've had a number of these and I'd be fine if the update only took a few seconds but they don't. I don't expect to have to wait an hour to use my PC. I've a feeling it might be if it's left with no power overnight but, it doesn't always happen and I've never had or read about a motherboard that needs constant power.
I have the latest BIOS is that know to have problems?
What is it updating exactly, why does it take so long and is it really going to make it unbootable if you turn it off during the update?
Each time it does it it reminds me of the G73 was when it came out, good but glitchy, and that perhaps I should have stuck to Gigabyte.
On final thing, considering this is an official Asus forum there seems to be a distinct lack of Asus personnel answering peoples questions.