For those of you that don't automatically upgrade to the latest and greatest, what feature would get you to upgrade to the new iPhone (5S or 6) that's released this year? For me it simultaneous talk/data. I had it on my Thunderbolt, and although I don't need it very often, now that I don't have it I really miss it. I never realized how often I multitask on the web while on voice calls. What about you guys?