Click to see Spoiler:
Merle will remain MIA for the rest of this season. Although Shane is killed pretty quickly in the comics, he'll still be alive when this season ends. Darbont thinks there's more to explore with the Rick/Shane/Lori triangle. I haven't read the comics, but they mentioned the Governor, a sadistic, evil character and, when Darbont was asked if Merle would become the Governor, he didn't confirm or deny! There are also a few other fan favorites from the comics that will probably show up next season as well.