In less than a month, I will turn 55. In the real world. this is not a notable birthday -- no one's throwing me a party. But in the world of marketing, television programming, and advertising, it's a number of great significance. Having already moved out of the 18-49 demographic, I am about to move out of the key 25-54 group and become part of the dreaded and nebulous 55+ category. What will happen between now and next month that will change how advertisers and networks see me? I will still have more disposable income than ever. I will still watch lots of TV (although not much live), go to lots of movies (where I actually do see the commercials), and buy lots of stuff. I will still use numerous mobile devices, from my BlackBerry to my iPad2. I will still subscribe to Netflix, have three DVRs, stream video fairly often, text at least a few times every day, and spend a good deal of time on Facebook. I will still play games with my 12-year-old son on Playstation 3 and Wii. And I will continue to try new brands (at least those that acknowledge I exist). But advertisers, marketers, and networks will now see me as though I was part of my father's generation. I am not. Ignore me and those like me at your own risk. • When my father was my age, his son had already graduated from college, moved out of the house, and started working. I have a 12-year-old son, and have probably spent more money this year on video games than on food. • My dad grew up during the Depression, which resulted in a whole different way of seeing the world, consuming products, and dealing with money. I grew up during the 1960s and 1970s, in the heart of the middle-class Baby Boom generation. • My dad was in the army during World War II. I turned 18 the year we got out of Vietnam (part of the last group to actually get a draft card, and the first generation in many years not to go to war). • I was also among the first generation to grow up with television (my dad grew up with radio). In short, I'm part of a completely different generation than my father, with a completely different mindset. A few years ago, the Council For Research Excellence (CRE) released its landmark Video Consumer Mapping Study, which dubbed 45-54 year-olds "Digital Boomers." This group tends to watch television similarly to the next older age group, but uses computers and mobile devices more closely to the next younger age group (I was fortunate to help spearhead this study, along with my colleague Shari Anne Brill, as co-chairs of the CRE's Media Consumption and Engagement Committee). These Digital Boomers are now moving into the 55-64 age group. Adults 45-64 should be one of the key advertising demos. It is no coincidence that the average median age of the broadcast networks' prime-time audience falls smack in the middle of this group. A lot of people don't realize they are also the heaviest DVR users. The very idea of age being the primary driver of media usage, however, may well be an antiquated notion. My son just moved out of the 6th grade. When I was his age, my classmates' parents were generally similar in age, income, marital status, and even number of kids per household. Life stage didn't matter much when it came to measuring media, because people of a certain age were typically in similar life stages. When I look at my son's class today, I see parents who range in age from their mid-30s to late 50s, half of whom are divorced. I have friends who are the same age as me, some with no kids, some with kids in college, some married, some divorced, some single. I have friends in their 30s and 40s with kids the same age as mine. Whose media habits are closer to my own? When it comes to radio listening or what I load on my iPod, probably someone closer to my age (unless my 12-year-old son is in the car). When it comes to home computer use, what movies I go to see or download, how much I text, or my video game usage, there are almost certainly more similarities to younger parents with children the same age as mine. Without a kid my son's age, I doubt I'd be so familiar with Youtube or whatever dot com he asks me to check out today. My TV viewing and time-shifting habits are probably somewhere in the middle. Some shows, such as "Modern Family" and "Glee," we often watch as a family pre-10 p.m. (although not necessarily on the day it initially airs). Other series, such as "Sons of Anarchy" and "The Walking Dead," I watch after my son goes to bed. What's the bottom line? I forget. Oh, yeah, life stage age trumps age, but if the industry insists on using age/sex as a key metric, 45-64 should be among the most significant groups to target.