It's official over 96.6 percent of the people want to rejoin Russia as claimed by the election officers.

ETA: The BBC has a translation of the the referendum ballot paper.

The discussion of enacting sanction by the European Union are beginning today, starting with travel restrictions and asset freezes of certain Russian officials.

UPDATE:

I speculate that we'll see which sanctioning tools the United States will use against Russia, later today.

UPDATE:

President Obama signed an executive order freezing the assets and banning visas for a number of Russians deemed to be responsible for the seizing of Crimea or otherwise interfering in Ukrainian sovereignty. Among those targeted were several top aides or allies of President Vladimir V. Putin, and the White House threatened to go after more if Russia did not back down.

Source: The New York Times