I think the answer is "different", but a quick look at the ingredients list on both packages would provide the proof. I don't think they taste different, but I think the different manufacturing processes for each would require different formulations. The bars are poured into molds and allowed to harden, the kisses are pumped onto a flat surface and hold their own shape without the aid of a mold.
It also appears to me that the bar chocolate has a more uniform appearance when you look at a section of the bar you've broken in two, and the kisses have a somewhat "grainy" appearance to the chocolate.