Its red.

 

It's a dark place, monster roam the land all variaty of monsters for that matter..
Pigmen
Slimes
Blaze's
Ghasts
Spawners
Nether wart farms
PvP
and it's Red, like Ike said. :p

 

It looks just like sp nether, cept with lots of unnatural lava flows from nukes

 

It looks like glowiness.

 

http://www.minecraftwiki.net/wiki/The_Nether

 

The nether will be completely, 100% regenerated on February first.
Until then, yea, it's really used up. I've heard there's barely any mob spawners left at all.

 

I've heard of at least 4 different spawners that were left right before the nether kinda stopped being used, and I think they are the last four period. This was last I heard, I only know the whereabouts of one of them, so for all I know, there could only be one.

 

I know of 3 and I hid them all cleverly.

 

The nether smells like magma. And not the good smelling magma either.

 

It looks and sounds like hell.

 

http://www.minecraftwiki.net/wiki/The_Nether