Biden is not going to run. And Obama appearing next to him at Biden's White House announcement likely means that the Justus Department will not indict Hillary. Hillary, IMO, has now locked up the nomination. She has the money and the majority of the D-Team support.
Now it is a direct Clinton vs Sanders fight, with Sanders ahead in some of the white-dominated states such as New Hampshire. However, Clinton will get 99% of the African-American, Hispanic and LGBT votes, which will enable her to destroy Sanders. I think Biden will be the VP candidate, in case Hillary wins the Democrat nomination.