When the USAirways-America West merger was first announced in May I noted that a key detail was a planned cash infusion from a credit card partner in the neighborhood of $300 million.

It was curious that the partner wasn’t named, while Bank of America was already partner to both airlines.

So, despite the Charlotte Observer calling the news “somewhat unexpected”, it shouldn’t be all that surprising that Juniper Bank (which issues Frontier and Airtran cards) will become the issuer of the USAirways card.

Taking the place of Charlotte-based Bank of America will be Juniper Bank, a subsidiary of British-based Barclays PLC, which agreed Monday to pour $455 million into the merger between US Airways and America West Airlines. In exchange, Juniper will have the exclusive right to market the US Airways credit card beginning in 2008, after a two-year transition period in which both banks can offer US Airways cards, according to regulatory documents filed Monday.