G has introduced some bonuses for adsense referals: - When a publisher who signed up for Google AdSense through your referral earns their first $5 within 180 days of sign-up, you will be credited with $5. - When that same publisher earns $100 within 180 days of sign-up and is eligible for payment, you will be credited with an additional $250. - If, in any 180-day period, you refer 25 publishers who each earn more than $100 within 180 days of their respective sign-ups and are all eligible for payout, you will be awarded a $2,000 bonus (bonus payouts are limited to 1 per year). You can read the full description here: http://groups.google.com/group/Inside-AdSense/browse_thread/thread/b613ac3b7c3ee45c?hl=en
The new referral payouts are good news for the referring publisher. Previously if you referred someone to AdSense you only got paid if they made $100 in 180 days - a big task for a new publisher. The new $2000 bonus is also a particularly attractive prospect.