Texting in Class

I've been hemming and hawing about how best to deal with the now-epidemic texting and Facebook phone and laptop issues in class. We don't have an official program policy (and likely won't, as this is up to folks' discretion), but I'm going to try a new one this year and wonder what y'all think or if you'd be willing to share what you have in your syllabus (either in the comments here or in your own post).

Here's what I think I'm going to try this year:

"Technologies: Please turn cell phones and any other electronics off during class. You’ll be notified in advance if you should bring laptops to class for work; otherwise, assume you won’t need them. Texting, checking Facebook, etc. from your phone or computer means you’re not engaging in the daily activities of our course. If you are using your electronics during class, it will be marked in the gradebook and I’ll notify you after class or via email; two violations will equal an absence for the course, and each additional violation will accrue another absence. Thus, failure to adhere to the technology policies can impact your final grade."

Here's my thinking: I had sometimes been calling students out, even making them put their phones on my desk if it got bad or after a warning or two, but that felt too much like policing. What I like about this policy is that it's not about disrupting class, and since I'll notify students, it's not something that would shock them at the end of the semester. It also seems a policy one could use at their discretion (for example, my husband asked if I meant if I ever see their phone, and I meant more when I observe prolonged use [meaning, to my mind, more than the cursory check of who just made one's phone vibrate--as they never do really turn them off]).

I don't think this policy is without drawbacks, it's something to work with. What have you tried that works well? How might you tinker with this one and why? Or should there be no policy in our syllabi at all on this?