Lawrence Lai/ABC News

Morning Money Memo…

Black Friday holiday shopping will start on Thursday this year at many big retailers. Target and Toys 'R' Us are the latest chains to announce they will open on Thanksgiving day. Other big retailers are also planning to make an earlier start before Black Friday. Toys 'R' Us will be open for business at 5 p.m. on the holiday. For the first time Macy's will open most of its stores Thanksgiving evening.

Best Buy, Kohl's, Target and Sears will also be open on the holiday. With Thanksgiving coming later than usual, this will be the shortest holiday shopping season in a decade, Retailers who are concerned about gloomy consumer spending forecasts are responding with early openings. Toys 'R' Us is sending out a 28-page circular in newspapers Wednesday.

Amazon plans to start Sunday package delivery in several big cities, announcing a partnership with the US Postal Service. The service began this weekend in the New York and Los Angeles metropolitan areas. Sunday delivery will be expanded to other cities next year. The partnership is a business boost for the struggling Postal Service, which lost billions of dollars this year. Amazon has spent heavily on new warehouses in the US and around the world so that it can speed delivery of products.

The recent stock market rally shows no signs of fading. The Dow Jones Industrial Index closed Friday at a record high. Stock averages have been up for the past five months in a row. Futures rose this morning. But some analysts warn a pullback may be overdue. The data firm FactSet says stocks in the S&P 500 are trading at a price-to-earnings ratio of 14.7 times analysts' expectations for the next year's profits. That compares with a 10-year average of 14.1.

International stock markets were mixed at the start of the week after unexpectedly strong US economic growth and the monthly jobs report reinforced expectations that the Federal Reserve will start cutting back stimulus soon. Investors were also waiting for any changes from a four-day meeting of China's communist leaders.

This may be a volatile week for Twitter. After a very strong start on Thursday, with a stunning gain of 73 percent from its IPO price, Twitter shares fell more than 7 percent on Friday. Many analysts and investment professionals say Twitter is over-priced, while others say it's virtually impossible to put a precise valuation on the money-losing firm.

The price of oil is down again this morning on global futures markets. West Texas crude fell to $97.45 a barrel and is down 11 percent in the past three months. Gas costs for motorists continue to drop.

Richard Davies Business Correspondent ABC News Radio abcnews.com Twitter: daviesnow