We recently installed Data.com Clean in SFDC and several standard fields (i.e. D-U-N-S Number, NAICS, NAICS Desc, Tradestyle, SIC Desc, Year Started, Ownership, Ticker Symbol and Rating) were added to the Account object, but these new standard fields are not available in Marketo. Please make these new fields available.
The Data.com Fields not replicating to Marketodiscussion explains that these fields are not being seen by Marketo because they were introduced in a new version of the API that Marketo is not using. So perhaps this Idea will be implemented when Marketo supports the newest API.