I received this call today. They hung up as soon as I answered. I reversed the call an got a recording stating press 9 to block this call. I called the only company I deal with which uses the name cardholder and they said the call did not come from them. Also this web site doesn't have a choice for credit card companyies.
Definitely not legit cardholder services. The partial voicemail i got said " This is your final notice as it relates to the financial stimulus, so press one now to take advantage today."