Not surprisingly, in a 5-4 decision the court's conservatives ruled that political gerrymandering is outside of their jurisdiction, and refused to block the states from doing so, saying that that was a job for either the states themselves, or Congress. In a more surprising decision, again 5-4, the court blocked the Trump administration, at least temporarily, from including a citizenship questions on the census form, basically saying that the reasons given by the administration for including the question didn't make sense in light of the questions that have been raised about the real reasons for adding it. It is unclear what will happen next, as the administration has said that the forms need to go out by the beginning of July and there doesn't seem to be time for the additional lower court hearings that the High Court asked for. Whether the forms will go out without the citizenship question on time, or be delayed, remains to be seen.
Of note is the fact that Chief Justice Roberts wrote both decisions, showing just how much power and influence he has at this point, with Kennedy no longer on the court.
ETA: The Census opinions are among the most complicated that I have ever seen. Here is how the court describes how it breaks down as to the various different parts of the decision: "ROBERTS, C. J., delivered the opinion for a unanimous Court with respect to Parts I and II, and the opinion of the Court with respect to Parts III, IV–B, and IV–C, in which THOMAS, ALITO, GORSUCH, and KAVANAUGH, JJ., joined; with respect to Part IV–A, in which THOMAS, GINSBURG, BREYER, SOTOMAYOR, KAGAN, and KAVANAUGH, JJ., joined; and with respect to Part V, in which GINSBURG, BREYER, SOTOMAYOR, and KAGAN, JJ., joined. THOMAS, J., filed an opinion concurring in part and dissenting in part, in which GORSUCH and KAVANAUGH, JJ., joined. BREYER, J., filed an opinion concurring in part and dissenting in part, in which GINSBURG, SOTOMAYOR, and KAGAN, JJ., joined. ALITO, J., filed an opinion concurring in part and dissenting in part. And here is the decision itself, if you feel like wading through a lot of legalese: http://cdn.cnn.com/cnn/2019/images/06/27/census.pdf
"Among the tales of sorrow there are yet some in which amid weeping there is joy and under the shadow of death light that endures."