One of the things that always irked me while roaming was the high cost of international text messages. It is bad enough that carriers flay you with $3.50/minute roaming calls they also charge you about $0.50 per outgoing text message.
AT&T is starting to be a little bit more progressive by now offering a international text messaging plan allowing for 50 text messages in 90 countries for $10 a month. After the first 50 it is $0.40 per additional message.
I am really waiting for the day that carriers realize that the cheaper they make roaming the more people will actually use it…