Google 4th-qtr revenue misses Wall Street target

By Alexei Oreskovic SAN FRANCISCO (Reuters) - Google Inc's revenue grew 15 percent in the fourth quarter but fell short of Wall Street's target on declining online ad prices and unfavorable foreign exchange rates. Shares of Google edged up 0.1 percent to $510.66 in extended trading after an initial dip on the news. Google's advertising revenue has come under pressure as more consumers access its online services on mobile devices such as smartphones and tablets, where ad rates are