I started with Red Box D&D and then moved on to 1E Advanced.  10+ years later Vampire came along and I realized I much preferred wound levels over hit points.  Now I can go either way.  I think tastes are always changing, but maybe as you get older you don't get hung up on the little system details anymore.  As long as the game mechanics are serviceable, I'm more interested in how the story plays out.  At least, that's been my experience.  

Pete

The first two Rpg's I played were Vampire TM and AD&D 2nd, at the time I liked both, but for different reasons; now I wouldn't play them at all.
What I'm trying to say is that at least for me, my early experiences did not whatsoever shaped my tastes in Rpg's.

I´m puzzled by the question.
And some answers.

There is only one obvious answer to the OP, and it is "yes" for every single one of us.

You are socialized as a roleplayer by past experiences. What else could there be? All the stances you take, are stances developed from your gaming past.

It´s a process going on and on and on. And it starts with your first games, obviously.

Settembrini, that's both true and trivial.

The question was: Will the first RPG we like and play for any length of time henceforth be the yardstick by which we measure all the other games we encounter later on?

For some people the answer is yes, for others it is no.

OK, I see.

I started with Advanced Fighting Fantasy and WFRP, and I do think that certainly had an influence on me in terms not necessarily of what I thought was cool (a few years later, I played 2300AD and thought it was the best thing since sliced gold), but did probably ground me in a certain style of play that meant I found certain systems weird or intuitive or what have you.

AD&D, for example, I played for a long time but never really got. This was probably not helped by me never owning the rulebook, but whatever. Shadowrun, on the other hand, I had no trouble getting immediately and rolling up characters.

However, I would like to think that as time has passed, the fact that I still likie WFRP a lot is not because it was my first game, but because I actually do like it. Sort of like how I thought Swords of Shannara was Top Stuff when I was about 10 but even thinking back now realise how awful it was. Whereas another book I thought was great when I was 8, The Restaurant at the End of the Universe, I still like.


(Actually, thinking about Shadowrun, it's amazing how easily we did take to it. Looking at that 1st ed rulebook now, there are all sorts of things I can't figure out, but we just filled in the gaps at the time without thinking too hard on it. A bit like when I watched the Transformers movie again with my flatmate and he said "I'm sure I remember this film making a lot more sense at the time".)

Woo, I'm full of anecdotes today.