From Barr’s four page letter.

Honestly, that’s about the worst possible outcome.  I was kind of hoping for some resolution, one way or another.

So apparently the report, according to Barr, finds no evidence of conclusion and declines to make conclusions on obstruction.  Of course, Congress is going to demand the full report, and that fight will take weeks if not months if Barr is unwilling.  The House Intelligence Committee wants to know if there is evidence of a compromised Presidency.  Everyone wants to know why Manafort provided the polling data to the Russians.  Even the Republicans want the supporting documentation so they can determine if Obama or his staff did something wrong with the FISA warrants.  And everyone wants to know what is happening with the investigations by Federal prosecutors in New York, Virginia, and Washington DC.

It basically appears that Mueller punted.