Wall Street notched another win today as optimism for a strong earnings season continued to grow. The Dow Jones Industrial Average (DJINDICES:^DJI) moved up 76 points, or 0.5%, to close at 15,300, its highest closing mark in three weeks. Alcoa (NYSE:AA) got things started off on the right foot, beating adjusted earnings and revenue expectations in its report last night, though shares finished down 0.1% today after gaining 1.4% in the run-up yesterday. A large restructuring charge caused the manufacturer to report a $119 million loss. As the first Dow component to report and the worst-performing this year, Alcoa's beat seems to have reassured the market. Analysts have also lowered the bar significantly for earnings this quarter, as the consensus for S&P 500 companies' earnings growth is at just 2.9%, down from 6.1% in April. In the first quarter, those stocks grew profits by 5.4%.

Oddly enough, Alcoa's strong report did nothing for itself but sent shares of fellow traveler Caterpillar (NYSE:CAT) up 2.6%. The two are the worst-performing Dow stocks this year, as they are subject to many of the same market forces, including the vagaries of the business cycle, construction demand, and growth in China. Consequently, Alcoa's earnings beat is a good reason to bet Caterpillar could also top expectations. Analysts are projecting earnings per share of $1.72 and revenue of $15.04 billion, both sharply down from a year ago, when the heavy equipment manufacturer reports on July 24.

Cisco Systems (NASDAQ:CSCO) was also a winner today, gaining 2.2% after announcing a partnership last night with Microsoft to "accelerate the deployment of private and hybrid cloud infrastructure worldwide." The project builds on past work between the two tech heavyweights on data centers, and should give the world's networking leader a further competitive advantage.

Fellow tech blue chip IBM (NYSE:IBM) didn't fare as well today, however, falling 1.9% after getting downgraded by Goldman Sachs from "buy" to "neutral." Analyst Bill Shope argued that pressures on emerging growth markets and high profit-margin areas make the company less appealing. The tech giant has been struggling of late, falling 8% after a disappointing earnings report last quarter, and also took a hit following rival Accenture's recent guidance cut, as both event seems to indicate that the IT consulting industry may be flatlining. IBM will report earnings July 17; analysts are expecting EPS of $3.78.

Fool contributor Jeremy Bowman has no position in any stocks mentioned. The Motley Fool recommends Cisco Systems and owns shares of IBM. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.