Just got home from SDCC....bummer someone beat me to it because I got some photos of the dynamite up the chicken as well.
Anyway, I took a bunch of photos of it, will share them here asap. But, I also talked to one of the Sideshow employees who had some of the scoop on the figure.
He said that it will go up for presale in Aug/Sept and will ship in early 2013. He also said that it definitely comes with a 2nd right hand that is holding a Baretta (like in the WIP photo). He also said that as far as he could recall, the red Deadpool PF figure does NOT come with a 2nd head.
However....he also said that they are also doing a grey/black X-Force Deadpool. It will be the same base figure shown here, with no rubber chicken, with the head sculpt shown in the WIP photo. He also said that the X-Force DP will come with "a number of weapons that are interchangeable" including the ability to hold a katana, not just the guns.
He expected both to sell for somewhere in the range of $350.
Hope that helps!