Speaking of the "kings of the Earth" (us) and the City of God,
"...They will bring into it the glory and the honor of the nations..."
- Revelation 21:26
I see this as a reversal of Babel, but only in the sense of a re-gathering. This is not a homogenization in which we all become bland copies of one another. I think this includes the survival of different languages.
My "existence proof" of this is what God says about his word:
"Forever, O Lord, your word
is firmly fixed in the heavens."
- Psalm 119:89
God's word is comprised of multiple human languages, and therefore multiple languages will exist forever.
Will we be able to speak with one another? Many options here...
We have, after all, eternity to learn each other's languages... No real problem there, and actually a lot of fun (picture a lot of pointing, pantomiming, falling on the floor laughing at mistakes in imitating words...).
There may also be a "universal language." Some of my Jewish friends claim that it will be Hebrew; I'm agnostic about that.
In any case, I don't think communicating will be a problem. Telepathy, anyone?
We'll find out how it all works, in an instant, I believe. Much like Jesus did for the disciples on the road to Emmaus. I'd like my mind opened and cleared out, that's for sure. I know that within the context of His resurrection and the disciples belief being blinded by fear, Jesus opened their minds to the scriptures. I'm just using this as an example of how I think it might happen. On that Day when we stand before Him....will I have questions. No. I'll be a puddle. I will become undone - which is good.
Blabbing and thinking at the same time might not give you a clear idea of what I am saying. Maybe I do need coffee after all.