Google's years of Dominance are numbered?

Mitch Ratcliff writes on his blog at ZDNet about Google's Dominance ending very soon. He says:

contraction of the dominance cycle is real, as computing is the continuation of earlier information ages that have lasted roughly half as long as the preceding ones: Bureaucratic management and storage of information (approximately 100 years, from 1850 to 1950); printing (1500 to 1900); scribal recording networks maintained by church and mosque (600 to 1450).

At that rate, IBM did its 30 years, Microsoft its 15, and Google may get its 7-8 years, which are now about to end... Mitch's comments are based on comments posted by Rich Skrenta on his Blog.