[fritterdonut]

Won't the Nether be expanded once the overworld is expanded?

I don't know. I've seen people say that it isn't going to be expanded, and I've seen people say it will be.
Don't think Intelli has a actually announced whether it will be or not.

[Deimos]

Please use the "Not Now" option within the client to stay on 1.8 until this thread is updated to say otherwise.

Can we get a 24h update warning so we can get our affairs in order?

[meepers]

So what will happen if we DO update? wont be able to play minerealm?

[Prodigy9]

So what will happen if we DO update? wont be able to play minerealm?

At least until Minerealm's servers update to 1.9. Alternatively, you could make a backup of your minecraft folder before updating, and you should be able to move the current folder back once you've updated, in order to switch from 1.9 to 1.8.

[eplawsl]

If the regular world gets expanded, the nether will as well, that's not something you can change without some serious modification (unless bukkit added support for something like this, which would still be serious modification and unlikely). If we didn't get a nether expansion we wouldn't even really be vanilla anymore, we'd be tapioca or something.