My neighbors just invited us to their son's bar mitzvah. This is at once a bigger and a smaller deal than you might imagine. Bigger because we wouldn't have even noticed if we hadn't been asked - we talk all the time, and I think of them as friends, but I don't even know their first names. So, just getting the invitation we got was a very pleasant surprise and we're very happy to have gotten it.
Smaller because we were given the appropriate invitation - we were invited to the synagogue to see Binyamin be called to the Torah as a bar mitzvah and to the kiddush afterwards. If they have a lunch for family and close friends, we were not invited - nor would we expect to be. Like many Orthodox bar mitzvahs, this is a simple affair focusing on the boy being counted as an adult. Although we will toss candy. :)