It's been known that Flynn had served as Director of National Intelligence under President Obama and that Flynn had been removed from that job because of his disruptive management style. White Flyun had been considered a brilliant counter-intelligence officer, he did not adapt well to being in a management position. It's possible that Flynn had undergone some sort of change, but Obama apparently felt he had to get rid of him -- and to warn his successor, for whom Flynn had served as a close adviser during the campaign.
Sean Spicer responded to the news by acknowledging that Obama had "made the President aware he was not a fan of Michael Flynn." But Spicer quickly tried to change the subject to questioning why Obama allowed Flynn to keep his security clearance. That really does not follow: being a bad manager does not mean you are a security risk.
Meanwhile, we await Sally Yates' testimony before the Senate