I had this problem aswell...stuck at 1 second. I forced shut the update program by task manager in windows. I unplugged the device and tried to start didnt work.

I then saw that the update program gave me a message that i could plug in the device and it would "recover" it....it said this can take up to 15 minutes. I did connect it again and waited about 5 mins and all of a sudden i had a full working n900...updated and all.

Mine stuck at 1 second remaining and then said "Software update failed"

When I unplugged my phone the four or five dots appeared and it looked like it was going to boot then froze. I removed and reinstalled the battery and it booted the old firmware. I am stuck at 1 second remaining again.

It failed again.

I'd suggest using flasher instead - it seems to be more reliable than NSU.

I used Jayford's instructions and was able to reflash. I lost all of my installed apps but everything else seems to be intact.

His instructions are here http://talk.maemo.org/showpost.php?p=470585&postcount=8

I followed that but it failed. There are some having the same problem and others are successful and there are others having other issues after this recent update. mine's brick now.

And if the USB icon doesn't apear anymore (only the dimmed Nokia screen), is it hopelessly bricked? Or is there a trick to get the USB icon back?

I got the same 'stuck on 1s problem' followed by the prompt saying the software update failed.

So I'm following jayford's advice in post #8 but I get the prompt getting stuck with this message: "Suitable USB device not found, waiting"

I have pressed the 'u' key and see the nokia logo with the USB sign on the top right while doing this. I've tried different usb ports also.

I'm using windows vista 32bit...

I did the update on a friends linux pc, went thru smoothly