One planet, two stars

When we are going to approach to the binary system Kepler-16 (image source) we'll see two different stars: the largest of the couple, the star A, is a K dwarf with a mass of about 0.69 solar mass and about 0.65 Sun's radius, and a little red dwarf, the stra B, with a mass of about 0.2 solar mass and about 0.23 Sun's radius. But when we'll arrive at about 0.5 au from the gravitational centre of the binary system we'll see a great surprise: a little planet with a mass of 0.333 ± 0.016 and a radius of 0.7538 ± 0.0025 those of Jupiter⁽¹⁾.

In this momenti is very difficult to suppose the properties⁽²⁾ (like composition and surface temperature) of Kepler-16b, but the most important thing is that Kepler can discover, using the transit technique, also a planet around a binary system! I think that this is the principle reason becuase the paper was accepted by Science. And it's clear that all nerd and sci-fi fan think about Skywalker family's planet, Tatooine:

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Press release: Nasa, Kepler
Two interesting posts from SETI by Laurance Doyle and Franck Marchis

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(1) Doyle, L., Carter, J., Fabrycky, D., Slawson, R., Howell, S., Winn, J., Orosz, J., Pr sa, A., Welsh, W., Quinn, S., Latham, D., Torres, G., Buchhave, L., Marcy, G., Fortney, J., Shporer, A., Ford, E., Lissauer, J., Ragozzine, D., Rucker, M., Batalha, N., Jenkins, J., Borucki, W., Koch, D., Middour, C., Hall, J., McCauliff, S., Fanelli, M., Quintana, E., Holman, M., Caldwell, D., Still, M., Stefanik, R., Brown, W., Esquerdo, G., Tang, S., Furesz, G., Geary, J., Berlind, P., Calkins, M., Short, D., Steffen, J., Sasselov, D., Dunham, E., Cochran, W., Boss, A., Haas, M., Buzasi, D., & Fischer, D. (2011). Kepler-16: A Transiting Circumbinary Planet Science, 333 (6049), 1602-1606 DOI: 10.1126/science.1210923 (pdf)
(2) In the paper we can read that the high density suggests a greater degree of enrichment by heavy elements. At the other hand

Nevertheless, for any age greater than 0.5 Gyr, the planet’s interior would include 40-60 Earth masses of heavy elements according to standard planetary models⁽³⁾. This would imply a composition of approximately half gas (hydrogen and helium) and half heavy elements (presumably ice and rock).

So I think that is not so correct write in press release

Kepler-16b is cold, gaseous and not thought to harbor life

also because

it more difficult to estimate the age [of star A] with theoretical evolutionary models

The surface temperature (170-200 K), instead, seems more certain.
In every case Kepler-16b is a death planet...
(3) Fortney, J.J., et al., Planetary Radii across Five Orders of Magnitude in Mass and Stellar Insolation: Application to Transits, Astroph. J., 659, 1661-1672 (2007)