EntertainmentThe following is a guest post from AARP entertainment writer Austin O’Connor.  Here’s one thing I’ve learned during the first two days of the network upfronts in New York City: Attending these annual glitzed-up PowerPoint presentations — when the nets unveil their upcoming fall lineups to assembled advertisers and brand partners — as a writer for AARP is a little like attending a high school prom as a parent chaperone. Sure, you’re there, but it’s really not about you. See, for …