I just found 2 iridium ore in the nether, is that supposed to happen? (I've yet to find any in the overworld, but it looks so alike to sliver/lead ore i've probably seen a few and gone straight past them).
Not that I know of. Iridium ore was added to the generation by gregtech and I doubt he would leave it there if he didn't want it. Most people I know of use the nether to get there iridium because of the smaller chunk sizes increasing the amount available in an area, and is easier to see against the netherrakk
Iridium generation in the Nether is a bug with GregTech, or rather an oversight that is corrected in later versions of GregTech. There are some in the overworld. It spawns about... I'm wanting to think one ore every five chunks?
i didn't know that the iridium ore generation in the nether had been 'fixed', but i did read somewhere that there were going to be huge meteor craters in the End where iridium would be more common. Take that with a pinch of salt until someone confirms.
I didn't know that iridium in the nether was unwanted, but alright then. I am playing with the game updated to 1.4.5 but I haven't done much in the nether to notice it being fixed, but I do know that the End has asteroids floating out in the distance that you can go to for special Ender ores that you can get iridium from.