Consumers in ten states (California, Colorado, Connecticut, Florida, Kansas, Maine, Massachusetts, New York, Oklahoma, Texas) won't be affected, since laws in those states forbid the practice (it seems that gasoline station owners here in Massachusetts got a different memo, though).
Visa/MC contracts still state that merchants have to have the same policy across their business. For larger chains that have a retail presence in these ten states, the prohibition on surcharging there means no surcharging anywhere else either.
From NBCNews:
Visa and MasterCard have rules that require retailers to handle credit cards the same way in all of their stores across the country. That means a chain with stores in any of the 10 states where a surcharge is banned would not be able to have a surcharge at any of its stores.
The settlement also states that merchants have to apply the same policy equally to their other cards that they accept, such as AMEX or Discover. Since AMEX still prohibits surcharging, if a merchant accepts AMEX they cannot surcharge for credit cards.
From NBCNews:
The National Retail Federation points out that under terms of the settlement, a merchant who adds a surcharge to purchases on a Visa or MasterCard would have to do the same with American Express cards. But AMEX prohibits surcharge fees. So a merchant who accepts American Express as well as Visa/MasterCard would not be able to surcharge any of those cards.