I just bought my first smartphone and dataplan after being just a basic cell phone user for ~20 yrs. When I activated the plan I did not include the texting options as part of the plan. But I see an app in the market for MSN Messenger (among others). Presumably using this would be part of the data plan. So what's the difference between "texting" and IM ? The only thing I can think of is that IM won't work unless the particular IM app is actively running whereas texting may be always on like a voice channel. Thanks!