I am trying to create a formatter that will convert the date format shown to an NSDate object:
NSString *dateStr = @\"2010-06-21T19:00:00-05:00\";
NSDateForm
Honestly, you'll just have to change the source data (removing the colon) before running it through the formatter. Your original date string is non-standard and none of the time zone format strings will work properly on it.
You can see the valid inputs on unicode.org.
ZZZ e.g. "-0500"
ZZZZ e.g. "GMT-05:00"
Nothing for "-05:00"