Where did you find this pic from? I don't think it is a bomb/missile, it doesn't have any kind of fins to guide it or anything. Space isn't an issue either so I don't think there would be any popout fins.
The attached cables make me think its some kind of EW pod or research/data gathering equipment, but that doesn't explain what the pointy thing coming out the end is. Maybe some kind of measurement probe? If only we had a pic from the backside...
I think you are onto something. It could be a device that simulates a munition, and the 'probe' in the back could actually be a data antenna that beams data back to the bomber or a ground station. By the way, the image is from 81.cn.