LEADING THE DAY: Facebook is launching Deals, its service to rival Groupon and LivingSocial, in five test markets today, the New York Times reported. Deals will be offered for events with a social emphasis, such as concerts, and can be purchased with a credit card or with Facebook Credits. The service is expected to launch in Atlanta, Austin, Dallas, San Diego and San Francisco, the markets Facebook lists on its Deals homepage.

Republicans question cellphone tracking: Five Republican members of the House Energy and Commerce committee have sent letters to mobile companies including Apple and Google to ask about tracking on cellphones, The Hill reported. The lawmakers sent letters to Apple, Google, Research in Motion, Nokia and HP about their privacy policies.

Committee chairman Rep. Fred Upton (Mich.) and Reps. Mary Bono Mack (Calif.), Marsha Blackburn (Tenn.), Greg Walden (Ore.) and Lee Terry (Neb.) signed the letters. Bono Mack chairs the Energy and Commerce subcommittee on trade; Walden chairs the communications subcommittee.

YouTube to start streaming movies? Entertainment news site TheWrap reported that YouTube is launching a streaming movie rental service. The report said that the service would not be a subscription-based like Netflix, but would let users rent individual movies as with Apple’s iTunes.

According to All Things Digital’s Peter Kafka, Sony, Warner Bros. and Universal have all signed deals with YouTube, though the video site has not made deals with Fox or Paramount.

Netflix ties Comcast: In a report to investors yesterday, Netflix announced that it added 3.3 million U.S. subscribers, tying Comcast as the country’s largest subscription-based video service. That was slightly under analysts predictions, as many had expected the company to surpass Comcast. Netflix stock dipped in pre-market trading.

Netflix CEO Reed Hastings raised concerns about data caps in a letter to investors, saying that it would be smarter for companies to limit speeds during peak times than to cap data altogether.

Sony unveils two Android tablets: Sony is getting into the tablet game, revealing two tablets running Google’s Android 3.0, or Honeycomb, at a press event in Tokyo, the Associated Press reported. One of the tablets sports a 9.4-inch display, while the other has two 5.5-inch screens and folds like a book. The tablets — code-named the S1 and the S2 — have not been given an official price.