Although we don't believe in timing the market or panicking over daily movements, we do like to keep an eye on market changes -- just in case they're material to our investing thesis.

The Dow Jones Industrials (DJINDICES:^DJI) were up about 24 points as of 10:45 a.m. EST, as investors celebrated the Thanksgiving holiday by continuing the bull-market run that has sent the Dow to four straight all-time record highs. Strong economic data from the Conference Board's Leading Economic Index helped put investors in an optimistic mood, and Home Depot (NYSE:HD) and Caterpillar (NYSE:CAT) could stand to gain from favorable trends even as McDonald's (NYSE:MCD) saw its shares sink this morning.

The 0.2% gain in the Leading Economic Index wasn't nearly as strong a gain as the index has posted in previous months, but it nevertheless was better than economists had expected to see, and extended its streak of gains to four consecutive months. Conference Board Director of Macroeconomic Analysis Kathy Bostjancic pointed to the financial, housing, and manufacturing industries as contributing the most to the positive trend in the LEI, but Conference Board Economist Ken Goldstein pointed to weak consumer demand as holding back the economy from faster growth.

In particular, a big gain in building permits was the second-most important factor in the LEI's rise, and that should be a natural boon to Caterpillar's heavy-construction-equipment sales, and to Home Depot's building-materials business. Home Depot has repeatedly demonstrated its superiority in making the most of any economic condition in its home-improvement business, but solid home-construction figures can help it grow its business with contractors, and add new support to sales and profits. As for Caterpillar, it has suffered from the reluctance of companies to make construction-equipment purchases, but a combination of low interest rates and more favorable conditions could bolster growth going forward. The LEI is, therefore, likely an important reason why both stocks are up modestly, with Home Depot rising 0.3%, and Caterpillar up 0.6%.

Falling, though, is McDonald's, which lost almost 1% in early trading. The fast-food giant is facing an increasingly competitive environment, with Burger King releasing new menu options, and moving to open stores in France, hoping to cash in on improving conditions in Europe. Meanwhile, hard-hit Yum! Brands (NYSE:YUM) has finally started to see things turn around in China, reminding investors that the problems it faced with the Avian-flu scare are temporary. McDonald's will have to work hard to sustain its own growth as hungry competitors ramp up their own efforts.