I think what translates into humor today is the antiquated stereo-type of a nerd. Nerds used to be exactly those guys. What happened? The whole terminology has changed and evolved with society. We as a whole society are enamored with technology driven products and the line that separated someone like Lewis from someone admonishing him has thinned drastically. All the things that separated those outcasts or "nerds" have come to be some of our most endearing facets of life. I don't feel I even need to mention computers, comic books, and video games, all of which have become some of the biggest industries in the modern world. But do nerds exist anymore? Yes, they do.

What I find nerds to be accustomed to is, a universe that they create around an interest, and out of insecurity and misunderstanding of society around them lose themselves in that world. They keep anyone else out to empower themselves in an environment they can control. They take an obsessive, but unproductive obsession in said interest, and expect everyone else to be envious of their prowess.
It's easy to understand really. In most cases, these people are not gifted, or interested in "traditional" means of goal achievement (sports) and basic human nature drives them to something that gives them a effort/reward paradigm. You can admire that in mostly anything, and understand its charm.
I think the word "nerd" now has shifted into someone who has a higher level of expertise in a particular thing than the average person. For example, I am a hockey, wrestling, music nerd - no doubt. What is doesn't mean is that I expect everyone to have the level of understanding that I have for these subjects. I also can share opinions without condensation. I can also enjoy learning more about these subjects without limiting me to my own concrete opinion. I may get excited about a particular subject and I may lose my composure about somethings, but I have to understand that it's not my world exclusively. There is no truth, there is only you, and what you make the truth.
To sum it all up. The word nerd has changed. It has trans-mutated into a cultural head nod to anyone who you can go to for advice outside of yourself about a topic. What used to be anti-culture is now popular culture. The people in Revenge of the Nerds are now running our country, our media, and shaping our society to what it is now. What makes the nerd is the insecurity that gets turned into anger. It may change the label of nerd into something different (which we will tackle later this month) The line between society and nerds are now one in the same, making the definition of it as obsolete as a church in Philadelphia.
I'll leave you with a perfect example of what a nerd is/used to be:
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