Updates for Season 2:
Here are the big bits:
Skill Rating is changing from 1-100 to 1-5000
Tiers are being introduced (Bronze, Silver, Gold, etc.) that you cannot fall out of (except Master and Grandmaster)
Competitive Point rewards are being multiplied by 10 (goes for banked CPs too) - but so is the cost of golden weapons
Sudden Death is being removed
Note: Season 1 ends this Thursday, 18th August, and Season 2 begins 6th September - although that date could still change.