The US Constitution was written in the days when it took James Madison three days to travel to his nearby political friend, Thomas Jefferson's house. That same trip can be made today in twenty minutes by car. Foreign policy with Europe in those days could be a problem as well, as it took several months for Executive policy to reach Ambassadors in England and France - often events in the US would outpace communications. So it was wise at the time to include a provision for recess appointments as getting the Senate together could take weeks, if not months. Today? With modern transport? Not so much.

From the US Constitution, Article II Section 2:

and he shall nominate, and by and with the advice and consent of the Senate, shall appoint ambassadors, other public ministers and consuls, judges of the Supreme Court, and all other officers of the United States, whose appointments are not herein otherwise provided for, and which shall be established by law: but the Congress may by law vest the appointment of such inferior officers, as they think proper, in the President alone, in the courts of law, or in the heads of departments.

The President shall have power to fill up all vacancies that may happen during the recess of the Senate, by granting commissions which shall expire at the end of their next session.

As this graph from the Washington Post shows recess appointments have become a normal part of executive governance where it over-rides the need to 'advice and consent' of the Senate, and any potential interview of a Senate panel:

Source: Washington Post, For Bush, the Fun Begins at Recess.

The article notes that the last eighteen months of a Presidency usually ends in a frenzy of recess appointments. Recesses of the Senate have also become more frequent due to modern transport and communications as well as politics. So any break qualifies as a recess, rather than a protracted one that would necessitate and 'emergency' recess appointment of an executive official.

The Bush Administration argues that more positions should be able to be appointed without Senate oversight, there is probably an argument in that as government has grown drastically from what it was in 1787. By the same token, the management of the Bush Administration has shown little respect for the other branches of government and through this practice of recess appointments the Senate is losing its authority over appointments by the Executive. Which is an important check and balance.

This is an issue in the US because there is strong separation of powers between Executive and Legislative, even if the checks are often given force by party machines in opposition branches being in opposition to each other.

Something that is not unique to the US, it is the same in Australia as Andrew Bartlett's recent comments show.

But even so, the Australian Senate has no constitutional basis for overseeing appointments by the Executive - in fact until recently there was no check and balance on the Executive's appointment of judges to the High Court. Australia just does not have a strong system of checks and balances in its constitution.