If you read the US newspapers, as I have to for work, they get even weirder. The oddest thing is missing out the word 'on' as in 'The President will announce Tuesday that...' or 'we will be investigating Wednesday...' Why? What's Wednesday done?
Yet they're very formal - where we'd start off saying George Bush and then refer to him as Bush, they'd say Mr. Bush, note the full stop after Mr., which is pretty obsolete here. Similarly it's always U.S.A.