As someone stated, Dennis Ritchie can be mourned perfectly, without downing the death of another person.
It's not a popularity contest as someone suggested, it's more about the niche of people that you appeal.
For almost everyone that owns an iPhone, iPad or an iPod or any of those other iThings, Steve Jobs was the creator (sic) of those products. He appealed to the "consumer" part of the public. It's this same consumers that are mourning his death and hence you see such threads sprouting everywhere. People are continuously searching about Steve Jobs and hence you see blogs, websites (read marketers/webmasters) writing about him and trying to add as much content to it as possible.
Whereas, Denis Ritchie, only appealed to the technical crowd. More so, the extremely technical crowd. His developments were no doubt very important for us and contribute greatly to the IT world that we see today, but that doesn't mean everyone should know about him, or for that matter, mourn his death.
Dennis Ritchie was a pioneer in the computer industry on its own and there is no reason to resort to cheap tricks to highlight his accomplishments and invaluable contributions to the world. Ritchie is an absolutely historic person, among these who defined the base on which everything is running, no doubt. But I would say that Jobs' and Ritchie's legacies are not really that tied together since they were engaged in the different level of technology.
Ritchie was a technologist, who developed code architectures. Steve Jobs was a technologist, a visionary who worked with the amalgamation of code architectures and design.
'nuff said.