I miss my Treo and even the Touch. My company rolled out BBerries and pays our bill directly.

I wondered if I could take out my sim card and put it in another device of my choosing. I could use EAS like I did before. But, since I am on a BES plan with my device - can I buy another phone from ATT and have smartphone like features with the use of my sim card? Or will it not work?

I googled the iPhone 3G sim switch but reports say it won't work. What about other options like a Treo 800 that supposedly is coming?