DracWell:
Rudess didn't replace Moore... Sherinian replaced Moore and Rudess replaced him.
I read somewhere up there that DT is for people who play an instrument or are really into technical music. I agree with this to an extent. You obviously have to have a love for technicallity if you want to listen to it, because it's just not as boring and bland as the majority of music out there (i.e. the whole pop culture scene, past and present).
About the John's hair: I saw he got a hair cut and thought "Well, when Metallica cut their hair, they went soft. When Ihsahn cut his hair, they changed styles. When Kerry King shaved his head, they turned to shit. So this new album might not be the regular DT." I was wrong.