See The First Tweet From The New Pope Francis I

Newly elected Pope Francis I appears on the central balcony of St Peter's Basilica on March 13, 2013 in Vatican City, Vatican.

The new Pope, Cardinal Jorge Mario Bergoglio  who was announced as Pope Francis I.
And this is the first tweet from @Pontifex, the Vatican's Twitter account:

...find out what the phrase ''HABEMUS PAPAM FRANCISCUM'' means after the cut...

The Latin phrase can be translated as "WE HAVE POPE FRANCIS." Bergoglio is the first Pope ever elected from the Americas and the first Jesuit....see what the twitter account looked like before now HERE
Cardinal Jorge Mario Bergoglio also tweeted via his personal twitter account as seen below:

Last month he also posted this hilarious tweet:

...his personal twitter account has since been suspended, by twitter for reasons best known to them.