I just noticed that goldpassport site just changed the bonus offer listing from old GPxxxx format to Gx. And it appears (perhaps erroneously) that G2 is 1500 and G3 is 2000.

Example:

Hyatt Regency Sacramento
1,500 Gold Passport Bonus Points
February 1, 2005 - February 28, 2005
G2


Hyatt Regency San Francisco Airport
1,000 Gold Passport Bonus Points
February 1, 2005 - February 28, 2005
G1


Hyatt Vineyard Creek Hotel & Spa
2,000 Gold Passport Bonus Points
February 1, 2005 - February 28, 2005 Sunday through Thursday only
G3