I finished the book not too long ago, also. Without a doubt, one must instantly call upon (a very small pun intended) his/her memories of The Stand to see how well it stacks up against it.
Cell is a tighter narrative than The Stand in several regards. The focus of a wide spread genocide is more narrow, and, not surprisedly, more effective than The Stand's attempt to drive home the point through several inner stories. A reader really gets the feeling that King has learned to achieve more with less since his bulky The Stand days. Another fine example is King's decision to leave more to the reader's imagination. In The Stand, King made sure to make us all aware what the virus was, where it originated, how it was released, and how the definitive misuse of the ramifications by Randall Flagg. In Cell, many of those questions are either left for the readers to figure out, or they are, at best, satisfied only through the theories of main characters in the story even though many of the characters, villains, stages of story progression, and plot are similar to the former book.
Cell is a good zombie-like tale, and, due to popular culture zombie films by the likes of Romero and the original Twilight Zone, I am tempted to read between the lines and find sociological or even political metaphors in play. Could there be? King is certainly not known for such leaps into lecture, but, as suggested before, such themes have been cemented into the zombie genre.
Thoughts?