Every day, the Fortune staff spends hours poring over tech stories, posts, and reviews from all over the Web to keep tabs on the companies that matter. We’ve assembled the day’s most newsworthy bits below.

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  Early reviews of The Social Network, director David Fincher and screenwriter Aaron Sorkin’s adaptation of Ben Mezrich’s The Accidental Billionaires, has received rave reviews from Variety, The Hollywood Reporter and Rolling Stone. “A mesmerizing, bewildering and infuriating protagonist makes this movie about Facebook’s creation a must-see,” wrote critic Kirk Honeycutt. (The Hollywood Reporter)

• ThinkEquity analyst Aaron Kessler reports Wall Street is valuing Yahoo (YHOO) at “less than nothing.” (Barron’s)
• In other Yahoo news, CEO Carol Bartz went to bat for the company, addressing speculation of a troubled relationship with Alibaba, falling “product engagement,” and frequent staff turnover. Said Bartz: “I can’t tell you how many times I’ve gone to my assistant and said, ‘Do you know who this person is,’ and they’re about six layers down.” (We know: not exactly heartening.) (Paid Content)
• Ebay’s (EBAY) Lorrie Norrington, head of the core auction business, is leaving for “personal reasons.” When Norrington started in 2008, she was tasked with boosting growth, which has either slowed or even declined, quarter-to-quarter. (The Street)
• Some competitors and customers are concerned about Oracle’s (ORCL) overwhelming growth. Over the last five years alone, the company has acquired 66 companies, including hardware maker Sun Microsystems. (The New York Times)
• Research in Motion (RIMM) may use next week’s developers’ conference in San Francisco to launch its much-talked about BlackBerry tablet. (The Wall Street Journal)
• Adobe (ADBE) reported a 69% spike in quarterly net income but shares took a nosedive after the company cautioned that expected revenue for the current quarter would not meet analysts’ expectations of $1.03 billion. (The Associated Press)
• Twitter was temporarily crippled by a JavaScript loophole that would redirect your browser to a Web site with malicious code if users moused over a particular benign-looking Tweet. The bug has since been patched, and life in the Twittersphere, thankfully, has returned to normal, but questions remain over security. (Boy Genius Report)
• MetroPCS Communications (PCS), the fifth largest mobile provider in the U.S., launched its first 4G Long-Term Evolution (LTE) 4G market — Las Vegas — alongside its first LTE-capable smartphone, Samsung’s Craft. Features are pretty standard all things considered: 3.3-inch AMOLED display, GPS, Wi-Fi, Bluetooth 2.1, and 3.2 megapixel camera. Not so hot? The $299 price tag — and that’s after a $50 mail-in-rebate. (Boy Genius Report)
• Videogame publisher Activision Blizzard (ATVI) is the latest to join the growing list of businesses and organizations against a California bill backed by Governor Arnold Schwarzenegger that would keep violent video games from being sold to minors. Said company CEO Bobby Kotick: “We will never give up the fight for the freedom of expression our industry deserves.” (Joystiq)
• Facebook CEO Mark Zuckerberg says that 200 million users are using the social network for social gaming. (TechCrunch)