As earnings begin to trickle in, it’s looking like the advertising rebound of 2010 will have a significant impact on quarterly reports. That ad renaissance also helped media and entertainment conglomerates see a large return on capital investment, and in a report by trend analysis firm Needham Insights, analyst Laura Martin says that CBS and Viacom will have the highest return on capital among the major media companies in 2011. The report indicates that major media companies have seen cash growth between 24% and 94% over the past year, while earnings also rose healthily, between 11% and 41%. So companies like CBS and Viacom — which rely heavily on advertising — were on the high end.