Thankfully Capriles was not elected by the Venezuelan people, but is was close and the Americans won't be happy. Maduro may not be the perfect leader but if he can continue the Socialist movement built by Chavez then the country will be far better off than falling for the trap of the pro-America, pro-capitalism direction Capriles would take them in.
Already there's trouble with demands for a recount and violent protests causing 7 deaths. Maduro states that the U.S. Embassy has been "financing and leading all the violent acts" He says the embassy is backing what he calls "neo-Nazi groups" that he claims are behind the violence. The United States said earlier Tuesday that it will not consider the election results valid unless the vote-by-vote recount demanded by opposition candidate Henrique Capriles is done.
That's all fairly mild talk at the moment if you consider the US backed coup to overthrow Chavez in 2002, the US funded and helped orchestrate a violent armed uprising which toppled Chavez. The people didn't want this and it failed after only 48 hours. US aggression has escalated against Venezuela ever since the Chavez government moved to take control of the country’s oil industry in 2001 and use its revenues to fund programs meeting the needs of Venezuela’s poor majority, rather than enriching the Venezuelan capitalists and US oil corporations. Read more about this here
So Chavez's preferred successor Maduro is in the seat for now but he's also in for a fight from the elite capitalists who want a bigger foot in the door to suck away the countries oil wealth, and be assured they will do whatever they can to destablise the country and continue their propaganda against Maduro. Maduro has 3 choices- fall into line, be overthrown, or be Chavez II.