Sony note that it would "cause the update to stop" for some people, so they've now released "a new version" of the firmware. It's minor so it's still 3.41.
"...we have released a new version of system software update 3.41 with a very minor change (the version number does not change) on August 2. If you are experiencing such symptoms when replacing the HDD of your PS3 system, we kindly ask you to use the latest data and try again," posted SCEE's James Gallagher on the .
The world's PS3 population is safe once more - rest easy Sony fan.