Not sure if this is iOS 7 specific, but I thought it might have something to do with the new "block" feature. My girlfriend lives in Australia, I'm in the US. To avoid $.20 per text message, I'd like to only use iMessage when texting her. This works most of the time, but every once in a while it goes through as a green SMS message. I usually make sure to wait until send is blue and it says iMessage in the text field, but it still sometimes goes through as sms. I have the "send as sms" toggle turned OFF in iMessage, but this doesn't seem to always work. Is there anything else I can do, or block sms for this one contact only?