Stocks wavered on Tuesday before ending slightly lower, as investors mulled over a number of economic data points, as well as President Obama’s address to the United Nations General Assembly.

The Standard & Poor’s 500 index closed the day down one quarter of a percent to 1,697.42, while the Dow was off by 0.43 percent to 15,334.59, and the NASDAQ added 0.08 percent to finish at 3,768.25.

The President took the stage at the UN amid thick anticipation about a possible meeting with his newly elected Iranian counterpart Hassan Rohani, whose thorough lack of resemblance to his predecessor has raised hopes for actual progress on talks over the ancient nation’s alleged nuclear arms program.

A resolution to the standoff, or even moves in that general direction could ease tensions in an extremely volatile Western Asia, and in the best case scenario could lay the groundwork for an end to the ongoing Syrian civil war that has claimed 100,000 lives. Iran and Syria have a long-established and thoroughly institutionalized relationship that, it is thought, gives the former leverage to press the latter to sit down at the negotiating table with the armed opposition, thereby obviating the need for Western military intervention.

On the home front, the Richmond Federal Reserve’s regional manufacturing index dropped to zero, following a prior and unprecedented reading of 14, with huge drops in shipping, hiring, and new orders.

Meanwhile, the 20-city Case Schiller/S&P housing index for the month of July came in at 0.62 percent, shy of analyst expectations of 0.80 percent, and even further below the prior months’ reading of 0.88 percent. The lag is nowhere near disastrous, but any economic data related to housing has seen heavy scrutiny recently as a result of uncertainty over if or when the Federal Reserve will begin reducing its monthly asset and bond purchases.

The massively popular social media site Twitter left investors breathless today by announcing that it would be entering the market not on the NASDAQ as has been the tradition with most tech companies, but on the New York Stock Exchange instead. The highly anticipated event is expected to take place before the end of the year.

Meanwhile, one of the US big-three auto manufacturers Chrysler threatened its own IPO, subsequent to an ongoing unresolved dispute between the company’s two principal stakeholders, the Italian auto-maker Fiat, and the United Auto Workers.

For the second day in a row, financial stocks were the Dow’s worst performers, with JPMorgan Chase (JPM) , Visa (V) , and Goldman Sachs (GS) all ending the day significantly lower. Boeing (BA) was the index’s best performer, after its French rival Airbus announced its prediction that the global number of airplanes would double over the next 20 years.

Tech shares were a drag on the S&P 500, with Red Hat Inc. (RHT) ending the day nearly 12 percent lower, along with EMC Corporation (EMC) and Verizon Communications (VZ) .

On the NASDAQ the situation was the reverse, with big gains for tech stocks in the wake of the Twitter IPO announcement, with Facebook (FB) , Applied Materials (AMAT) , Zynga (ZNGA) and Yahoo! (YHOO) all ending the day significantly higher on heavy trading.