Attorney General William Barr's letter to Congress summarizing the major findings of the Mueller investigation has been submitted. You can read it here. Very briefly, the probe found no evidence for collusion with the Russians to affect the election, by Trump campaign or any other American, despite multiple contacts by Russians. On the matter of whether President Trump committed obstruction of justice in a variety of well publicized acts, Mueller did not find obstruction, but left the determination whether the acts met the legal definition of obstruction to the Attorney General. Barr and DAG Rosenstein made the decision that the acts did not rise to the level of obstruction, in part, because the underlying collusion was not found.
This will, of course, not satisfy the Democrats, but it certainly takes a lot of wind out of their sails. It's going to make their investigations look like double jeopardy and sour grapes. I expect we'll see some new weepy videos from Rachel Maddow.