From what I’ve found the 5.5 update broke millions of sites. This is why I generally do not update until after the first minor release for a major release and sometimes not even then. I just wait and let everyone else update so that the bugs can be reported and hopefully fixed. I’m working on a new site now that I must revert to 5.4… because fool that I am I keep sites in development up to date to make sure things will not break 😛
