The obligation on Purim is to "send" 2 foods to another person. The Mishna Brurah (Hilchot Megillah 695:4) says that one may exchange se'udah food with a neighbor and is yotzei (21) even if (and I admit, my understanding may be wrong) that sender is going over to that neighbor to share in the se'udah later and will end up eating his own food.
What if my neighbor comes over after megillah reading? Can I given him his mishloach manot while he is in my house and eat it with him in my living room?
Can this be taken a step further? If I am hosting my neighbor in my house for se'udah, does my serving him a meal count as both the se'udah for him and my "sending" of ready made food? Can I be mekayem my chiyuv simply by hosting friends at the se'udah in my house and serving them (since then I won't be using a shaliach).
Is there some essence to the mitzvah that requires taking it out of my house, or "sending" it away, or is the change in who eats it, regardless of location what is important?