“mthompson,” with the help of “GraziGamer,” has touched up and restored the rare Mattel Intellivision III brochure from Winter CES 1983. You can find the link to the PDF via AtariAge, here (and if there’s enough interest, “mthompson” may also do a print run).
Although Mattel promised both an upgraded Intellivision III and even a IV to better compete against more powerful competition like the Coleco ColecoVision, Mattel ended up selling off their Intellivision business in early 1984 after suffering heavy losses the previous year (one of many casualties of the Great Videogame Crash). While the Intellivision brand and products would continue to be a going concern until the end of the decade, no further work was done on either incredibly intriguing successor system.
If you’d like to read more about the Intellivision, ColecoVision, the Great Videogame Crash, and videogame platform history in general, you might want to check out one of my books, Vintage Game Consoles: An Inside Look at Apple, Atari, Commodore, Nintendo, and the Greatest Gaming Platforms of All Time.