The Millers seems to hint that it will branch out beyond annoying-parent jokes, but if the lazy crudity of the jokes is any indication, we don't have all that much to look forward to.
The Millers is definitely shooting for the lowest common denominator. The jokes are crude and broad. The pilot includes a running gag about whether or not mom farted.
There's plenty to sustain The Millers over what could be a pretty long haul. The show has both star quality and stars who know how to work the material.
With a generic title like The Millers, this show clearly isn't promising innovation. Viewers who enjoy familiarity will be satisfied and sometimes pleasantly surprised.
The humor is driven mostly by a relentless slapstick vulgarity, particularly concerning the flatulence and sex habits of parents. If you've got a high tolerance for those sorts of jokes, it is funny indeed.