You're not applying your standards equally across the board. If the CCD is able to be used as a sensor for digital cameras it's merely a shrunken version of technology already available that allows it to be integrated into a consumer product. When the fabrication process improved and allowed more complex circuits to be placed in a smaller space the PC was born. But when it's the PC, which is nothing more than a product that was made possible by the shrinkage of existing semiconductor technology, you (rightly) consider it a revolutionary invention.
When talking about impact on society, you've got to be insane to suggest that the cell phone is just an evolution of the telephone. The cell phone is an evolution of the telephone like a TI-89 calculator is an evolution of the abacus.
And you may not think Roomba is revolutionary, but that's because you're thinking small. The first PC's were little more than calculators. There was no Photoshop, DIVX, MP3, WWW, Google, Nero, Word, Excel, Powerpoint, Oracle, iTunes, Mouse, 3D or even any kind of GUI, Flash, clock speeds measured in megahertz, let alone gigahertz, hard drives (of any size), etc., etc., etc.. It took thirty years for the PC to become the essential do-everything tools in nearly every home in America that they are today. The first PCs didn't do much and hardly anyone had one. What you mistakingly dismiss about Roomba is it is the first useful consumer robot ever made. And if you consider the exponentially increasing pace at which technology physically shrinks but expands capability, it shouldn't take too much imagination to see where Roomba will lead us, just as the PC has. Consider this: If the Xbox 360 had been around in 1998, seven years ago, it would have been the fastest super computer on the planet. Think of that. The most powerful supercomputer on the planet today that costs tens or hundreds of millions of dollars will literally be a toy in seven years.
I think you've got it backwards. Revolutionary new inventions are coming at a faster rate than ever before simply because semiconductors are becoming the foundation of our society. The only time in history that has seen a jump in technology that even comes close to what we're seeing right now is when the world moved into the industrial revolution. And the industrial age will barely be a blip on the radar compared to the information age.