The original big three - there is another

 In talking about the big three, I should mention that there was actually a fourth - The Magnavox Odyssey2.  It first came out in 1978, making it part of the original three with the Atari 2600 in 1977, and the Intellivision in 1979.  It was the lowest selling of the three and, even though it lasted until 1984, by the time the Colecovision came out in 1982, it was already largely forgotten. 

It had 8-directional joysticks more akin to early computer joysticks, and came with a built in keyboard.  The cartridges also had a handle to make them easier to remove.  One of my friends had one of these so I was able to play a few of the games. 

But with the choice of this, the Atari 2600, or the Intellivision, the choice was clear for me.