Adding a Joint Owner at ING Direct

Jim at Bargaineering described how he and his wife combined their ING Direct accounts into one. It was done by adding a joint owner to one of their individual accounts.

How much can they have at ING Direct and still be FDIC insured? It's at least $1 million: $250K in each of their two single accounts and $500K in their joint account (see FDIC example).