I thought Emperor were kinda boring live, but it was expected. Borknagar was pretty cool, but I'm not super familiar with them. Witchery. dude. awesome.
Yeah, the mushiness of the production is something I've really grown to love...I think Anthems would suck if it was all clear and stuff. The squishy overpowering nature of it all gives it a kind of strange, mysterious beauty.
In the case of Emperor's older albums, one could very well make an argument for the production adding to the atmosphere of the whole affair.
As for IX... it's a good album. Closer to what Zyklon tried to pull of than much of the Emperor material out there IMO though. Difference being that it really really really worked on IX and created something worth listening to.
I think much of what pissed me off about the 1st Zyklon was that Samoth could have done better. There was just this desire to have an album where something other than Emperor name recognition was the major point. Hopefully, they at least surpassed Myrkskog on the new one.