What goes up must indeed come down, and even though the decline was modest, the S&P 500 Index (SNPINDEX:^GSPC) came down today, breaking seven consecutive days of gains. You can't win 'em all: a phrase perhaps best illustrated by today's bleak technology sector, which takes all three spots on Tuesday's worst-performing S&P companies. 

Open-source software provider Red Hat (NYSE:RHT), known primarily for its Linux operating system, helped the index break from its winning ways, cratering 4.8% after a Citi analyst spooked investors with a bearish update to his opinion on the stock. Citing simply the lack of a positive catalyst in the near future, as well as what essentially amounts to a lack of innovation in its services, the downgrade -- from a buy rating to a neutral rating -- struck a nerve on Wall Street. 

Investors also booed yesterday's decision from salesforce.com (NYSE:CRM) to raise $1 billion via convertible senior notes, as the sales management company fell 2.8% today. Fresh off a year where the stock jumped nearly 70%, managing growth is vital to share performance. Today's message: The market doesn't fully support how Salesforce is going about financing that growth. With a CEO who acquires social-media advertising companies for nearly $700 million, as Salesforce did last year, it's understandable for shareholders to have a few concerns.

The crushing blow of unflattering analyst commentary also struck Apple (NASDAQ:AAPL) shares today, as they lost 2.2% following a reduction in earnings estimates by Jefferies. Setting a $420 price target -- only $8 below Apple's current price -- the investment firm thinks sales may disappoint after performing supply channel checks. On top of that, Apple's dominance in the tablet market seems to be fading, according to research outfit IDC, which predicts that Android tablets will ship more units than iPads this year.