On the hardware front the 600 models will get “AeroVac Technology” for an improved vacuuming system, an improved cleaning head module with better brush design and airflow, and a pop of color on the top.
The iAdapt firmware has been updated as well and the 600 series will ship with the latest version. The 600 series looks more appealing than the 500s, will be more efficient cleaner, and its bin will have to be emptied less often, but most of the key features are the same. The 600 series is still designed for up to 1200 square feet, they work with the optional virtual walls, have the same cleaning techniques as before, and a new bot will still bounce a bit too hard into the leg of that expensive couch you just bought.
The 650 and 660 models will feature scheduling, so that the Roomba can run on the days and times required by the user.