Incoming data shows that Huygens’ instruments were functioning nominally throughout the descent. From this morning’s (EST) press conference, this statement by Jean-Jacques Dordain, ESA’s Director General:

“The morning was good; the afternoon is better. We were an engineering success this morning, but we can say this afternoon that we are also a scientific success. We are the first visitors to Titan, and scientific data that we are collecting now shall unveil the secrets of the new world. In fact we have got on the ground station data from Huygens long after the touchdown, more than two hours. I must say that we are short of ground stations! The batteries are much more solid than the number of ground stations which can receive the signal. Cassini has just started to deliver the data collected by Huygens, and we might be able to see the results during the night.”

And this fascinating detail from Emily Lakdawalla’s weblog for the Planetary Society:

One thing that may have helped the probe last a long time was that it appeared to stay unexpectedly warm. At an elevation of only 50 kilometers (about 30 miles) above the surface, her interior was still at a balmy 25 C (77 F), despite the outside temperature being a frigid -180 C (-290 F). [Project scientist Jean-Pierre] Lebreton wasn’t ready to say what this might mean. It could be overperformance of the spacecraft, but it could also mean a wide variety of unexpected things about the atmosphere. For those of you who like instant results, I think you’ll be disappointed on an answer to this question, because after all Huygens was a mission focused almost entirely on Titan’s atmosphere, so it’s going to take a very long time to synthesize scientific conclusions from all of this.