Looks like many people loved the epic, high level tone of the campaign setting. That attracted me too especially the Unlife, a properly inhuman faceless menace, but also the sci fi underpinnings of the setting helps me see the setting as real which is actually important to me. As a GM I have to believe in the setting, I have to be able to suspend my disbelief or else the prep work becomes a chore. The Shadow World hits that mark for me (as does M-E) so much so that the setting seems intuitively true. It all seems to make sense to me.
The biggest problem I have with the setting is that instead of all those substandard (i.e. below the very high standard of TKA's work) modules & sourcebooks there should have been more detail on Jaiman (Urulan, Saralis, Lu'nak, Wuliris Sourcebooks along the lines of Emer 1 & 2 or Xa-ar or even cloudlords or the Iron Wind) I am well aware that its not Terry Amthor's fault, but its the only serious complaint I have. I hope SW makes enough money for Terry to continue working on expanding it. I want it just popular enough to make Terry's life comfortable, but not popular enough to have Forgotten Realms style cannon lawyers everywhere.
I really hope the new RM rules work out & don't further fragment the RM fan base. Shadow World needs a healthy happy publisher & I have nothing, but good will for them. Since everything TKA has produced for SW over the last 15 years or so have been even better than the original run that drew me in in the first place.