In short, by the exit polls:

• PiS (the current ruling party, right-wing) got the most votes, but cannot rule alone, nor can rule in coalition with the alt-right party Konfederacja by a decent margin (212 mandates total vs. 231 needed to have majority).
• The opposition parties (center-right Koalicja Obywatelska, center-right Trzecia Droga and leftist Lewica) together have majority. They know they have to make a government together, the question is whether they can overcome their differences. They did suggest strong coöperation during their campaigns.
• Highest-ever turnout (72%) in the elections.
• The accompanying referendum (a device to have more funds for promoting ideas by the current ruling party) a total failure (40% turnout—voters had to explicitly opt-out of participation!).