I don't know why but I kept getting download errors when trying to update to 1.93 last night. My wireless was working fine on my laptop and I tried rebooting the PS3 several times, still no go. Hopefully today it works, if not I'll just do it from USB.
I was having the same issue. As soon as I disabled option to search for media servers (I had two running in another room), I was good to go. It may have been a coincidence, but it's worth a shot.