There are two kinds of this gift, as I call them, Harley_Angel and Remmy.
One is to edify the believer. It brings one closer to God. It is an unknown language given to the believer for when they pray. It's their perfect prayer language and expresses their heart to God. No, they do not know what they are saying. The gift helps when one does not know
what to pray. It intercedes for them.
The other is to edify the church. This is what Paul talks about when he says there must be an interpreter because it is for the church. God will give the message to the individual to speak, and He will give the interpretation to another (or sometimes the same person). When Paul talks about order, I believe he's talking about the "holy hush" God creates before it happens. The first time I saw this, I was awe struck. The church was at the climax of worship.. all crying out to God and praying out loud and singing... and then all of the sudden, it went quiet. It was like God turned the volume down dramatically. Even the music stopped. And then the message came, and the interpretation. So when it is of God, He will create an order to it. And the language that is spoken of in this instance is often different from the speaker's normal prayer language. Cool, eh?
I don't see it as a bigger responsibility than the command to go out into the world and make disciples. lol The first is very personal, the second is very special. They both bring one closer to God. And as I said before, it doesn't determine salvation. Just like water baptism doesn't. Having it doesn't make you any better of a Christian, and not having it doesn't make you less of a Christian. But it's a good gift to have.