Grand Coalitions are practically an Austrian tradition, with the majority of governments consisting of the centre-left SPOe and centre-right OeVP carving up power and ministerial posts between them. (This was a reaction to the turbulent politics of the Inter-War period, when Austria was very ideologically divided). So a Grand Coalition is not really a surprising result.
More notably, the far-right Freedom Party (FPOe) has increased its share of the votes to 21.4%, in an election with asylum as a hot topic. This increase of 3.9% should be since in the context of the other far right party, BZOe, (set up by Joerg Haider splitting away from the FPOe) losing 7.1% of their vote, dropping to 3.6% (the BZOe have tried to become more liberal/libertarian recently). The new Liberal party, NEOS, did slightly better than the BZOe, while the Greens also increased their vote marginally. The biggest winner of the election is probably the businessman Frank Stronach who set up a political party ("Team Stronach") as his personal political vehicle, winning 5.8%. Team Stronach are an economically liberal, Eurosceptic party, though it's not focused on the immigration issue in the same way that the Freedom Party is.
The 4% threshold to enter parliament means that apart from the BZOe, all of these parties will get in. Despite the centre-left lead coalition, the right has grown in Austria, with various strains of populism doing well. Having continuous Grand Coalitions probably doesn't help: without a clearer contest in the centre ground, the political space in opposition is left more open to populist parties.
In the end this election brought even more of what the German election last week brought: continuity.