It's official! It is now acceptable to browse the web on company time.
Why?
Because there's a term for it, and people openly share web links stating "work safe". The very existance of this phrase, and it's continued use, implies that people expect their friends to stop work and read the web page they've just been sent.
Of course, this doesn't make it right, but it does show that it's become the norm. And it gives sysadmins and easy phrase on which to search when snooping emails for personal time wasting ones.