That's not correct. Everybody mono is a new "experimental mode" enabled for the radio songs this week by Snowden and These Arms are Snakes. In this mode, for any character you pick, the blocks on the track are the Mono blocks, not the regular puzzle ones. So in Pusher, you can shunt the mono blocks to the side, or in Pointman, you can pick them up. Both the Stealth bonus (not hiting any grey blocks) and the consecutive colour hit points have been disabled.
Last week's "mode" that Lavos is referring to, each song had a different "feature" applied to it, as listed at http://wiki.xairu.net/index.php5?title=Game_news
Basstation: 4 lanes for all characters.
All the Rage: 3x white/black blocks.
The Come Down: Mono characters only. No Stealth bonus.
Let It Breathe: Minimum match size is 5.
Freeride (all 4 songs): 1st person camera
As for whether this will be a new mode entirely, I don't know.