As reported by Universe Today.

Link and pics here: http://www.democraticunderground.com/?com=view_post&forum=1014&pid=1117701

R&K

Now that we've all had a few days to recover from our euphoria, it's time to ask: what does this mean? The last time we heard from Philae, I was there in mission control, watching through the glass as a graph of its bus voltage trended to zero. I'm not ashamed of the tears I had in my eyes at the end. Philae had worked very hard in its final hours, taking and returning new data until the very last moment. But there was a lot of science left undone; Philae's awkward landing position and various mechanical problems had caused experiments that depended upon reaching and penetrating the comet's surface to be incomplete.

They would be incomplete forever if Philae never woke up. But project manager Stephan Ulamec always expressed confidence the probe would eventually return to action. It wouldn't be soon -- their understanding of the geometry suggested that the comet must get close to perihelion before the lander would receive enough power to run its transmitter. Maybe as late as August, he said, but possibly as early as May.

Here we are: it's June, and the lander is awake and talking again. How did that happen, what is the lander's status, and what's next for the mission? Let's take these in order.
The wakeup

The last signal was heard from Philae at around 00:30 UT on November 15, 2014. Philae was in too much shadow for its solar panels to generate sufficient power, but the changing season and approaching perihelion were expected to improve the situation. Rosetta began listening for Philae in March. That Rosetta update described the conditions necessary for Philae to make contact:

http://www.planetary.org/blogs/emily-lakdawalla/2015/06171501-philae-is-awake-whats-next.html