Google Webmaster Tools notifications

How many types of messages does the Google webspam team send out?  

Watch this video clip with Matt Cutts from Google that explains the types of Google Webmaster Tools notifications that they send out. Each month Google sends out thousands upon thousands of emails and 90% of the notifications are related to black hat tactics. 

Types of Notifications:

• Google Black hat spammer notifications: 90% 
• Google low quality or no quality content notifications: 4% 
• Google hacking notifications: 3% 
• Buying links notifications: 2% 
• Selling links notifications: 1%