When you send a text to more than 5 contacts at a time, it becomes a Group Send and will be placed in your outbound Queue. The contact names will be summarized by the numbers appearing in the brackets as follows:

< # of Outbound Texts Still Pending / followed by Total # of Contacts in this Group Send >

You will notice the first number (# of Outbound Texts Still Pending) will count down to zero. When there are no more texts in the Group Send that are waiting to go out, the bubble representing that Group Send will move into the Record area - signifying that all messages have been sent out.

You may delete or edit any message waiting in your Queue at any time - even if it is a large Group Send in the process of being sent out.  When you press the delete or the edit button for any message (including active Group Sends) still appearing in your Queue, you will immediately cancel and erase all unsent messages.  Of course, any messages that have already cleared the Queue and have been transmitted to the mobile carrier networks can not be erased.