I just got news that Amazon Associates payment will be monthly instead of quarterly, beginning January 1, 2007.
Affiliates will be paid 60 days after end of each month.
For example, referral fees earned in January will be paid at the end of March, and payment of referral fees earned in February will be paid at the end of April.
It’s ironic that the Amazon Associates program has been one of the oldest affiliate programs around and yet it’s only in 2007 that Amazon Associates payment cycle has been reduced to a more typical monthly cycle.
Well, better late than never. 
Related posts:
Thank you so much for this post. I use the reviewazon plugin. Reviewazon is the easy and simple way to add amazon affiliate product to your website.