It appears that accessing the twitter API is not threaded in twhirl. So the UI is freezing while you update and then not clearing the UI queue so that if I was scrolling when you poll you suddenly allow all of those inputs (scrolling, clicking, etc) to replay and cause havoc in the UI. So, please flush the queue or prevent input (glass pan) and put up a wait icon while you're doing synchronous polling and/or thread the background operations
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