Zod has actually went down. It's still considered a high rune, but like, a low-end high rune. People don't really want Zod for Ber/Jah/Ohm/Vex, because Zod isn't as useful as they are, and the big Zod-poofing made everyone scared.
Cham isn't a high rune anymore. It's not very useful, so it's in line with ist/lo/sur which are like .5 runes. Um/Gul/Mal are like .25 runes, and so on. Vex is probably always going to be king of the runes.
It's like this
Vex>Jah/Ber/Ohm>Ist/Lo/Sur/Cham>Mal/Gul/Um
I think that clears things up for the most part.