Fellow Chicagoan President Barack Obama spoke for many when he said in a statement, "For a generation of Americans – and especially Chicagoans – Roger was the movies. When he didn't like a film, he was honest; when he did, he was effusive – capturing the unique power of the movie to take us somewhere magical."
Added the Chief Executive: "Even amidst his own battles with cancer, Roger was as productive as he was resilient – continuing to share his passion and perspective with the world. The movies won't be the same without Roger."
Oscar-winning director Martin Scorsese (The Departed) said in a statement that Ebert's passing was a personal loss, as well as "an incalculable loss for movie culture and for film criticism." He said Ebert, 70, had been a friend over the years in good times and bad.
"Roger was always supportive, he was always right there for me when I needed it most and when it really counted – at the very beginning when every word of encouragement was precious; and then again, when I was at the lowest ebb of my career, just as encouraging, just as warmly supportive."
But Ebert also kept a proper journalistic divide, Scorsese noted. "There was a professional distance between us, but then I could talk to him much more freely than I could to other critics. Really, Roger was my friend. Few people I've known in my life cared as much about movies."
Among those who Tweeted respect with heartfelt remembrances were Michael Moore, who said, "Roger Ebert. Millions of thumbs up for you, RIP."
"Roger Ebert was an excellent writer, a gifted artist and as nice a guy as you'll ever meet. Sad he's gone," Tweeted Jimmy Kimmel.
"It was a privilege to interact with you," screenwriter Diablo Cody also Tweeted. "Thank you for the support, the criticism, and the true love for the movies."
"You were an inspiration," Tweeted actress Alyssa Milano. Added comedian Dane Cook: "RIP kind sir. I give your life two enthusiastic thumbs up."
Fellow film critic Ben Lyons, who co-hosted At the Movies in 2008 and whose opinions had once been criticized by Ebert, offered nothing but warmth and respect.
"He was fiercely competitive and I felt sorry for him as his physical health deteriorated over the years," Lyons said. "He loved movies and wrote passionately about them until he passed. My thoughts are with his family."