From the Cleveland Plain Dealer's Brian Windhorst:
According to a source, there's been a Michigan State players meeting called for 6:45.
This is the sequence of events that has developed over the last hour: First word leaked out to WDIV that Tom Izzo decided to stay and that a news conference was set for 7 p.m. That morphed into a news conference likely coming tomorrow morning, but the news that he is staying didn't change. Since then there has been a report that Izzo was meeting with Michigan State athletic director Mark Hollis, and now a players meeting is reportedly next on the docket.
It definitely looks like a decision has been made, and taking into account WDIV's report and the fact that this news conference will reportedly be held at MSU, all signs point to Izzo staying with the Spartans.