Before the bell:

U.S. stocks were set for a slightly lower open Tuesday, as investors weighed a fresh batch of earnings results and awaited reports on home prices and consumer confidence.

Stocks began the week with a solid start, with the Dow inching toward the 12,000 mark on Monday. The blue-chip index has been on an upward trend since Thanksgiving, and is now within a stone's throw of 12,000 -- a level last seen on June 18, 2008.
While economic reports may continue to be lackluster in the coming month, stocks are likely to remain in an upward march as investors focus on strong earnings.
Companies: Before the opening bell, DuPont (DD) logged quarterly results that widely beat expectations. The company also hiked its forecast for the current quarter. The results boosted shares slightly in pre-market trading.
Verizon (VZ)'s earnings missed by a penny, while revenue fell 2.6% from a year earlier. Shares of the phone service provider slumped 1%.
3M (MMM) posted earnings that were down slightly from a year ago, beating expectations by a penny. Shares of the company fell 1% in early trading.
Johnson & Johnson (JNJ)'s earnings met expectations, while revenue slipped 5.5%. Shares of the company fell 1.5% ahead of the market open.
After the bell on Monday, American Express (AXP) reported earnings of 94 cents per share on revenue of $7.32 billion. The numbers fell a hair short of analyst estimates. Shares fell about 1% in pre-market trading.
Yahoo (YHOO) is slated to report the market closes Tuesday, and is expected to report earnings per share of 22 cents on $1.19 billion in revenue.
Economy: The Conference Board, a business research group, will report its January report on consumer confidence shortly after the opening bell. The index is expected to increase to 53.5 from last month's reading of 52.5.
World markets:

Oil for March delivery slipped $1.36 to $86.51 a barrel.
Gold futures for February delivery tumbled $18.50 to $1,326 an ounce.
The price on the benchmark 10-year U.S. Treasury rose, pushing the yield down to 3.38% from 3.41% late Monday.