(i) macro-statistics over 80-100 year time range have shown beyond doubt that as capitalism driven economies ride the productivity curve, the average workers’ burden (proxied by age of entering work-force, on-job injuries/deaths, average work hours/day, etc.) vs. their wage (proxied by purchasing power, standard of living) have increased. In a Marx hypothesized “capitalist squeezing value from worker” setting, this observation would not have been nearly as pronounced.

(ii) as innovation/productivity rise and average wage rate increase, a direct consequence is of course increased competition, not only for “capitalists” but also “workers”. Why would firms pay for a skilled punch-card programmer when a Java/Ruby programmer can achieve same output for 1/50th of the time? Increased competition doesn’t necessarily lead to increased worker toil since they are building off of a more productive platform (e.g. searching information on Google vs. searching for information in the 1970s).

Also agree with hazencage – big concern is whether income inequality resulting from the capitalists efforts becomes so extreme that the potential for the average or below average to move up becomes extremely small (Good article on this topic http://www.economist.com/node/15908469 )