Here is a list of iMessage problems;
1) If someone sends you an iMessage and your phone is switched off, then you won't get the message what so ever( even when you turn your phone back on you won't get the previous iMessages..)
2) You can't block a contact.
3) You can't exit a group!
4) You can't edit the group members(add/delete members)
Please Please Apple fix those stuff:)
I agree 100%!!! These issues need to be fixed right away, including iMessage being able to differentiate iOS 5 users versus non-iOS 5 users in a GROUP CHAT. Instead, they ALL count as text messages even if you know some of them use iOS 5.
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