viewers at home heard what you heard. that s right. doesn t make for great tv. not at all. now we have done it again. a couple farewells in the entertainment world, david letterman s final episode after 33 year run onair to mad men s finale. kim serafin at in touch weekly catches you up with all the good-byes and more if i spo spoke to her. kim serafin, thank you for joining us. david letterman has his final show wednesday this week. what can we expect that night in terms of guests and possible surprises, perhaps, want to talk about his legacy as well as he bows out? yeah, just really the end of an era. seems cliche to say. clearly with david letterman the end of the late night talk show, as we knew it. leno gone now. a whole new crop of people, younger people, people doing segments that are built for youtube viewing and internet