Don't see it happening and if it did it would be like 20 years away so I'm not holding my breath lol. That being said, I love Fallout 2. Fallout 1 is great and I'd like to see them both but if I had to choose one it'd be FO2.
After thinking a bit more. I'd say if Bethesda let Obsidian or another company do it, it is more possible to be within the next 10 years or so. But chances are it'd be a new game. Buuuut remakes and remasters are a huge money maker and Bethesda likes money so who knows.