Actually, it is commonly necessary, or at least more productive, to revert to previous versions until all applications and add-ons are on the same page. There's a reason that there are sites all over the net providing backdated versions. Type "revert to version" into your search engine and see for yourself how many thousands of instances you are able to find.
You don't ever want to go backwards with web browsers. Not sure you actually can, but if you could it wouldn't make any sense. You'd be losing whatever functionality the latest version has and would only make your compatibility issues worse, not better.
I haven't had any issues recently, nor do I use photobucket or a mac, but in the last year I can think of at least 4 times where I've needed to revert to previous versions of Flash, Chrome, FF, and Skype. To tell people they should never do it is simply false. Sometimes doing so is the only option that works.