The Novation Luanchpad really brought the concept of grid based performing to the masses - tied together with the rise of Youtube as a musical distribution network, the first really big one was Madeon's Pop Culture sample mashup - (46million+), to M4SONIC's Weapon (45 Million+), bot have accrued enormous numbers of Youtube videos and took the concept of virtuoso performances on grid devices to another level.
We've been to the Novation offices and seen the commemorative framed award for over 300,000 units sold (as of to 2015) - that's a LOT.
In this documentary piece from Novation, they talk to the artists who have taken the Launchpad to the heart of their setups, and also added the API access to the LED lights to create more visual aspects to their Launchpads.
Madeon Pop Culture:
See the full article on the Novation website