After a brief period of uncertainty, the DNC issued a statement pouring cold water on the idea that Kaine had made the official announcement that was reportedly relayed by the caller but did confirm, notably, that Kaine said he is "increasingly likely to run."
"In response to a student's question, Governor Kaine told his law school class today what is already widely known which is that he is increasingly likely to run," said DNC spokesperson Brad Woodhouse. "However, no final decision will be made or announced until the governor has had a final round of consultations with folks about how he can best serve the President, the people and the causes he cares about; he is assured that the Democratic Party will be in good hands should he choose to make the race and leave the DNC; he has the support that would be necessary to mount a successful campaign and he completes commitments for travel and fundraising he has made to the Party and the President through at least the end of the month."
Kaine may announce his official decision as early as this week, according to recent reports.
Just another afternoon in the 24 hour news cycle.