As a Chicagoan for the last 27 years, I can confirm that Ebert was a respected fixture around town. Whether you agreed or disagreed with his particular opinions, any reasonable person had to respect his integrity and his strong voice.
I know I checked his movie reviews religiously before a home video purchase, though I disagreed on whether video games are art. He's wrong about digital projection, and the jury is still out on 3D.
Any way you slice it, he will be missed.