My ideal solution: start out with the widget prepopulated with the desired numer of tweets with the latest on top, and then start adding new tweets or scrolling with a 30 second interval.
Currently each item added is older than the previous one. This is a consequence of starting with an empty widget. If it was prepopultaed from the start, it could loop from old to new, rather than new to old which it does now and which feels counter intuitive.