U.S. stocks open slightly lower in thin holiday trade… Retailers fall on worry about weak “Black Friday” sales… Energy shares pressured as oil prices slip below $53

U.S. stocks slipped in thin holiday trade on Friday after a streak of gains as investors nervously eyed post-Thanksgiving sales to gauge how retailers will fare this holiday season, while worries about global demand hurt technology and energy shares.

Chevron (CVX) fell 1.9 percent tracking oil lower as OPEC gathered to discuss potential further supply cuts to combat falling demand. U.S. crude dropped below $53 a barrel.

Technology shares slid after signs of a downturn in global chip demand as STMicroelectronics cut its fourth-quarter outlook. Industry sources said Taiwan companies want to slash costs. The semiconductor index shed 1.1 percent.

The U.S. stock market was closed Thursday for the Thanksgiving holiday and is trading for half the day

The hostile takeover bid by BHP Billiton (BHP) to acquire mining-giant rival Rio Tinto (RTP) just got a step closer.  Australia, the headquarters for BHP Billiton and Rio Tinto, Ltd. (an RTP subsidiary), has approved the merger, which has sent Australian shares of Rio Tinto to jump 12%.  This morning, RTP is up another 3.8% so far on the NYSE.

Rio Tinto had rejected an earlier offer from BHP, but this was prior to the U.S. financial market descending into crisis.  Now, world-wide conglomerates are looking toward each other in order to secure their long-term support.

Zacks senior equities analyst Mario Ricchio covers both companies.  In his latest RTP report, he reiterated his Hold recommendation with this comment: "Cost pressures due to ongoing supply constraints are adversely impacting Rio's margins and profitability." 

About the possible merger between BHP and RTP, he said this: "Notwithstanding the associated anti-trust issues, we believe