Nick Janetakis takes on the most common argument against 80 chars per line:

It’s easy to think “wtf, I have a massive monitor, why should I limit myself to a standard that was created for punch cards in 1928 or terminals from the late 1970s?”

If that’s what you’re thinking, definitely give this a read. He makes a strong case. One thing is for sure, you don’t want to end up like this guy… 😆