Ok here is my issue. Say I update my old iPhone to iOS5 (or iPod touch), basically any device that I only use over wifi, then one of my friends who has an iOS5 device goes to send me a message, it's going to default to an iMessage right? (since the email address they have for me is the one I use for my Apple ID). This is all well and good if I am at home with my iPod Touch on wifi, but what if I'm not? If I'm out and about or without wifi access that message won't be received by me until I get home (or get wifi access somewhere). As I understand, you can choose to switch from an iMessage to normal sms by selecting the contact's phone number instead of Apple ID, but how does the sender know when the recipient is able to receive iMessages or not i.e. has a network connection. If I'm sending a message to someone who I know uses an iPod touch on iOS5 and has another cell phone and I want them to receive the message asap, I'm always going to chose sms as with iMessage I wont know how long it will be until they have a network connection.