Now that we can see the final regional breakdown in the Russian election results, it is much worse for Putin that it initially seemed. The 49% vote for United Russia includes the tallies for non Russian republics, such as Chechnya, where the 99.9% support for United Russia is clearly false.
Given that several districts in Moscow and St. Petersburg returned tallies of less than 25% for United Russia, then it seems like a reasonable working assumption that the majority of Russians in European Russia voted substantially against Putin.
When we consider that the election was not certified free and fair, amid widespread intimidation and pressure on independent observers, it seems more likely than not that Putin actually lost this election.
This creates a crisis of legitimacy.
Far from serving another two terms as President, it could actually be that this clearly fraudulent and stolen election marks the beginning of the end of the Putin era, even if not for the Kleptocracy that he has created and presided over.
This is totally unexpected. The belief was that Putin has sufficient popularity that he would be able to hold power more or less legitimately. It now seems quite clear that he needed the fraudulent votes in order to maintain a majority: without them he would have lost the election.
The press reaction is that he has "suffered a setback": it is much worse than that: he actually lost the election.