* Smartphone maker HTC is investing $300 million in Beats Electronics, the same company that releases various Beats by Dr. Dre audio products. HTC reportedly plans to incorporate the technology into future handsets. (All Things D)

* Twitter is updating the social network with two new features. Replacing the “@Mentions” tab are two new ones: “@username” (your user name) and “Activity.”  Like @Mentions did, @username will display when shows Twitter replies to you, but also include things like when someone follows you or when a user favorites your Tweets. Meanwhile, the Activity tab will show that type of information but for all the Twitter users you currently follow. (TechCrunch)

* Is patience with AOL (AOL) wearing thin? (The Wall Street Journal)

* U.S. antitrust regulators continue to look at Google (GOOG) and whether the Internet giant is giving its own products — Google Places, Shopping results, and Google Finance — preferential treatment over third-party offerings and also taking information from competitors and then pushing their services further down in Google search results. (The Wall Street Journal)

* Amazon (AMZN) released its new Cloud Reader, an HTML5-based web app that lets users read and buy Kindle e-books via web browser. The move makes sense considering the company only just recently pulled the Kindle purchase feature from its apps for Apple’s iOS. (Amazon and Wired)

* HP (HPQ) cut $100 off its TouchPad tablet, bringing the 16 gigabyte version to $399. (This is my next)

* Kids-focused daily deal site Zulily raised $43 million in funding at a whopping $700 million-plus valuation. (GeekWire)

* News Corp. (NWSA) lost $254 million on MySpace during its fourth quarter, before the ailing social network-turned-entertainment hub was sold off. (paidContent)

* From Google search to Netflix (NFLX) recommendations, 11 essential algorithms that make the Internet work. (Business Insider)

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