aldeb -- the CMS website is correct, you cannot directly report eRx incentive compliance using Amazing Charts (there are a few EHRs that allow this, as listed). You can still comply by using the "G code" (G8553) for eRx on every Medicare electronic billing submitted for an encounter that you used eRx for at least one prescription.
Dr_Dino --
Yes, still use G5883 for a minimum of 25 eRx events during the 2013 6-month reporting period (1/1/2013-6/30/2013).