Today in Tech: Google calls Siri a threat by JP Mangalindan @FortuneMagazine November 7, 2011, 8:42 AM EDT E-mail Tweet Facebook Google Plus Linkedin Share icons Fortune’s curated selection of newsworthy tech stories from the weekend. Sign up to get the round-up delivered to you every day. * Google GOOG chairman Eric Schmidt told the U.S. Senate antitrust committee that the iPhone 4S’s voice assistant, Siri, poses a “competitive threat” to his company’s business. Confessed Schmidt: “Apple’s Siri is a significant development — a voice-activated means of accessing answers through iPhones that demonstrates the innovations in search.” (Apple Insider) * Barnes and Noble BKS is holding an event this morning in New York City where the retail chain will reportedly unveil a hardware update to its Android-based, reading focused Nook Color tablet. Stay tuned for updates. * An insightful profile of LinkedIn co-founder and venture capitalist Reid Hoffman, who The New York Times dubs “the start-up whisperer of Silicon Valley.” (The New York Times) * Meet Tristan Walker, Foursquare’s head of business development and one of technology’s most prominent African American executives. (CNNMoney) * Instagram co-founder Kevin Systrom on international expansion and funding rumors. (TechCrunch) * Lessons from 12 New York entrepreneurs after a year in the business. (The Next Web) * Google’s patent counsel Tim Porter on why the patent system is broken. (The San Francisco Chronicle) * How online innovators are disrupting education. (Harvard Business Review) Don’t miss the latest tech news. Sign up now to get Today in Tech emailed each and every morning.