Speaking as an American, in the last quarter RIM had 4.8% of total smartphone sales GLOBALLY. They have a long way to go to climb out of this ditch. Falling from 11.4% to 4.8% is not a US only deal. And it's not a conspiracy. RIM isn't dead.

As someone who works in software, you also know how quickly things can go south - see Knight Capital...

Source - Worldwide market share for smartphones - Yahoo! Finance