The sleepaway camp I'm looking at for my DS for next summer doesn't allow cell phones, Ipods, game systems, etc... And for the price you spend for the kid to go to camp, they'd better be doing something other than text messaging the whole time!
My DS8 said a few kids in his class have cell phones. Honestly, there's NO reason for DS8 to have one yet. But, I'll probably get him a prepaid cell when he goes to middle school where activities finish up at odd times. Even then, I think we'll wait a few years before we allow text messaging.
Like you, Papa, I'd like my kids to be interacting with the world around them instead of text messaging all the time. I think we'll also have a basket where the kids can drop their cell phones (turned off) when they come in the house.
Then my kids wouldn't be visiting your house. I like them to have their phones with them so I can call or text at my convenience - I don't want you making that decision for me.
It's also way too controlling, in my opinion. Unless you are going to be actively socializing with a group of teenagers (and I can't imagine you would be) it's not impacting you in any way, and if it bothers your kids they should be the ones to tell their friends to cut out the texting. If they are old enough to have the technology they should be learning the skills they need to manage it with their peer group. Having Mom cut everyone off is not the answer.