Yes, there's still a Homeland without Brody--Showtime has just released a trailer that proves it!
Season 4 will mostly take place in Pakistan and Afghanistan, and be almost entirely free of Brody's family, as well, since it would be a bit awkward. ("So, how ya doin' since they hung your dad? School good?")
The trailer promises more political drama than personal drama, but they've pulled that bait-and-switch before. Bring on some Crazy Carrie!