I just upgraded from 3.0 to 3.2.1 today, a job that I have been putting off due to not knowing what the hell I'm doing, but was worried that one day 3.0 will be unsupported.
I had wordpress database backup send me a backup (with all boxes ticked) prior to upgrade as well as my weekly backups on my computer.
I upgraded WP from within my Bluehost account and lost website information.
I have followed both the below guides:
I am now definitely running 3.2.1 and have restored my theme but no information at all has come through from the backup restoration process.
I do use this site to make a small amount of money and am worried I will lose customers while it is down.