If only a couple of guys used a first-person pronoun that the rest of their school doesn't use, I would say they would sound weird in any country, wouldn't you? This obviously couldn't happen in too many langauges, though.

As to the meaning, I would say that they just want to sound like adult men a little too soon.

You can use 私 if you want to. Just don't say I didn't tell you when you go to Japan and gets laughed at for using it.

Like I said on another thread, I used 私 for the first time in recent memory recently, and it was a little weird.

That being said, I speak Japanese every day, and almost never need to use first-person pronouns.

I thought that I had read one time that in a professional context a man might say 私. While I don't remember where I read this, I thought the example was about a member of the government who would either refer to himself with ボク or 私 depending on the situation in which he was talking. This question is more to satisfy my own curiosity than anything. I'm a few years away from being any sort of professional in my home country, let alone Japan.

Weird thing is that I knew 僕 is used by young people, while 私 more by adult. So I started using mainly 私 since I am very close to 40 years old. In a couple of occasions I was told by native speakers that is sounded too "pompous" for me to use that word. Now I just use 僕...and I am always afraid to be too direct by using it (even tho MMM is right, it is easy to make conversations without using it).

That's not the way you change your pronouns. It sounds like you suddenly switched to use within your circle of friends. Am I correct?

We don't do that here. You basically use the same first-person pronoun all your life in your personal life. What we do is start using わたくし/わたし once we 're out of school and working. Even after that, most people stick with their old favorite pronoun to use in their personal lives. We switch'em around to suit the occasion.

Yeah, people need to learn that your first person pronoun isn't a function of you; it's a function of whom you are with!