If you haven't been keeping up with Liz Kolb's From Toy to Tool: Cell Phones in Learning blog, I strongly encourage you to go have a read. I used to say that I didn't want to do anything with my cell phone other than make and receive a few calls, but in the last several months, I've been very happy to discover (and use) many other features. Whether it's capturing posters at workshops (and sending to Evernote), keeping up with friends via text messaging, or showing off Poll Everywhere at a workshop---these are quite the versatile tools.
Meanwhile, "Acceptable Use Policies" in schools aren't necessarily keeping up. And, as Teacher Magazine points, out, schools are having to find ways to accommodate cell phones. I can't help that as features continue to be added (according to Liz, phones can now be purchased that have LCD projectors attached...and within 2 years, most/all phones will have broadband/DSL access and file storage), schools are going to have to find a way to make their peace and put phones to work in the classroom.