Ask HN: Best Width for Website?

I see a lot of people recommending something like 80 char width max. Or even lower. However, since each person is able to set the width of the browser, does this really apply to the browser? I mean, I have an 1080p 27" monitor, and I am fairly happy reading something like 90% width of that. No need to go all the way down to max. of 80 chars. Also, I think it looks horrible when the browser is full width on the monitor, yet a website forces the max-width to something like 940px. What is your personal preference on this?