An impeccable credit score was once a source of pride for bill-paying fiscally responsible Americans. Now as card issuers slash lines up minimum payment requirements and raise interest rates seemingly at random a stellar credit rating is rare indeed. Besieged by mounting losses on all types of consumer debt banks and credit-card companies are scaling back: According to Bloomberg 45% of all US banks reduced credit card limits for new or existing customers in 2008's fourth quarter. Issuers are attacking the problem in various ways but the net effect is the same: Americans are using less plastic. Citibank (C) is lowering ...