The consensus meme remains that a US government shut-down will have minimal economic effect if it is not protracted. Well, the US government shutdown is now 8 days old. To put things in perspective there have been 17 previous shutdowns through history and this is now the equal 6th longest - the average being 6.47 days.
As Deutsche's Jim Reid notes,
there continues to be a lack of obvious progress with Speaker Boehner refusing to back down on the budget and debt ceiling discussions without concessions from the President. On the other side the director of the President’s National Economic Council Gene Sperling has suggested that the President will not negotiate with any faction using the threat of default to force policy change.
On top of this polling continues to throw out mixed messages which can be used by either side to support their case - a recent CBS poll placed disapproval of congressional Republicans at 72% (vs Obama and congressional Democrats at 61%) whilst in the same poll 55% of responders said they believed the debt ceiling should be raised but with spending cuts. The latter stat gives Boehner some legitimacy in maintaining his stance.
The History of US Shutdowns: (via Wiki)