Doug from Aderit just informed me of a thread at WebmasterWorld where Google Advertising Professionals "were granted promotional credits to hand out to new clients. They also got to link to a page on Google.com profiling them, confirming their status."
There is more information as to what are Google Advertising Professionals promotional credits here and it starts off by reading, "These credits are one of the ways we help you bring in new business." In addition, Google does say that "While promotional credits are only available to professionals operating businesses in the United States, we hope to offer credits globally in the future." For a detailed explanation of how the "Credit System" works click here.