Syriza refuses to back down from its opposition to EU austerity whilst New Democracy and Pasok refuse to back down from their support for it. The parties are split 151-149 in opposition to the EU's austerity measures but that includes Golden Dawn which none of the other parties will deal with.
The Greek President has been desperately trying to get a unity coalition together but the Syriza leader was a bit put out that the only minority parties invited to join it were pro-austerity.
Experts predict that if a new election is forced, the anti-austerity Syriza will do even better and may even top the polls which is good news but it might not be enough. Lots of people voted for anti-austerity parties as a protest against the EU-imposed austerity measures that are making life hell for most Greeks but having made their protest and sent a message to the leaders of their traditional parties, are likely to vote as they usually do.
The Greek president, Karlos Papoulias, has suggested another technocratic government, which is another way of saying unelected dictatorship. This is vaguely reminiscent of the Greek military junta in the 60s where the King legitimised the military leaders who had taken over the country in a coup d'état. This time around the King is the President and the military junta is a team of unelected EU placemen.
If new elections are called it's likely to be in about a month's time. In the meantime Greece is still without an elected government and austerity measures are still being implemented by the undemocratic rump they've been left with which ordinary Greeks aren't likely to find particularly palatable and as we saw in June last year, when the Greeks get upset they do it in style.