The answer is "no."
My grandparents live in a small town (Colo) in Iowa where they grew up. It's about 50 miles NE of Des Moines. Population must be under 1000. Unlike San Francisco where it's hard to see a cell tower (and we have poor coverage as a result), cell towers dot the rural landscape here. It's actually amazing to see how many it takes to cover this area despite low population density – it's a lot. 1xrtt works relatively well out there. I was thrilled to have Internet access through the cellular network as there are no Starbuck's, McDonald's or Border's in Colo, and the gas station in town wasn't wired.
Back to SMS. I was at the grocery store with my grandmother and wanted to call ahead to order take out sandwiches from a restaurant on the highway back to town. I told my grandmother I'd call ahead on my cell phone. My grandmother has a cell phone, but she doesn't keep it with her. She only uses it in emergencies. I told her I was going to Google it through SMS. She looked at me like I was speaking a foreign language. I showed her how to do it on my phone. She looked at me as though I were from another planet. She didn't even ask what "Google" or "SMS" were. Google returned a very accurate result for the Country House Family Restaurant on US Highway 30 within seconds. I showed her the result. She wasn't impressed. In fact, she really wasn't that interested either.
Our consumer surveys test up to the age group, 55 years or older. Among those in this age group, 14 percent have used SMS. This is also an online survey so excludes those who may own cell phones, but are not online. My grandmother is 85. She's not online, but my grandfather was a regular user of WebTV until recently. They have a VCR, digital cable and cell phone which probably makes them tech-savvier than most in their late eighties.
Before we reached the restaurant, my phone rang. Well, U2's Vertigo started playing. My grandmother jumped two inches out of the passenger side seat. "What was that?", she asked. "That scared me." I don't think she'll be buying any ringtones in the near future either. I doubt her handset supports them anyway. She hasn't even commented on my ringback tone.