It looked like the Crazies was just another zoombie crapfest in the tradition of the whole "world's population gets infected with a virus...virus sounds good, right?...that makes average humans fast, pissed and hungry for human flesh" genre.
If anything it'd be a prion but that's something for the science and health thread.
I liked 28 Days Later (but not 28 Weeks Later), the Dawn of the Dead remake, and so on. But "I Am Legend" (shown roughly 12 times a day on TBS, apparently) showed me just how potentially shitty that stuff can get, so I take a pass on a lot of the new zoombie movies coming out.