The Urban dictionary defines CX as:
The awesome type of debate which has people speaking 250 words/minute and ensures an intensifying feeling throughout the round.
"This feeling inside... it's incredible... like a CX round."
There's also CX1:
awesome kid, leet one, the one marlon loves, yeah the one marlon likes to send porn links.
CX3: Trademark Speevie face. Includes eyes, and wide pouty lips.
And others.. Go here for the complete list:
Other people asked questions on various topics, and are still waiting for answer. Would be great if you can take a sec and answer them