I do public speaking every so often and despite how often I do, I still get very very nervous. I guess the question is do the nerves fade away over time? Or is it normal.
Yes, great question.
The law of habituation says the more you do something, the less you fear it. That works as long as you're not scaring yourself with fearful thoughts. I suspect that is what is happening in your case.
Your nervous system gets sensitized when you experience something fearful (threatening) in a particular situation. Your nervous system gets de-sensitized when you experience safety over time in a particular situation. So your nervous system is going to naturally get de-sensitized in a public speaking situation when you repeatedly go into it with a sense of safety. Public speaking is actually a safe situation, but when you add fearful thoughts, your brain interprets it as unsafe, and it has a harder time going through it's natural process of desensitizing. So those fearful thoughts can get in the way of "nerves naturally fading over time."
If you participate in a "lab" where you're practicing new thoughts and desensitizing your nervous system through repetition in a safe group with others who share your fear (like at SpeakMeister.com), that's a great way to get the nerves to fade.
So to answer your question, nerves do fade away over time as long as you're going into the public speaking situation with the right frame of mind.
Check out my blog on the most common "thought patterns" that cause anxiety and nervousness.