I would like to see it where you can 'quick reply' to an SMS message from the new iOS5 notification bar, without having to go into the full blown app. In addition to this, being able to compose a new message from within any app would be great. Currently there is a jailbroken app that allows for both of these functions called Tlert.
Also, additional group SMS/email support is a must for furthering the iPhone as a serious business device. Many businesspeople have groups they commonly send emails or SMS. The current implementation of having to click the + button and go through the list every time is time-consuming and tedious. Once a user has picked the first person they want to email or SMS, they should be taken back to the email/SMS app. If they then push the + button to add more people, the list of users should have checkboxes next to their names (or a dropdown if they have multiple methods of contact, each with a checkbox). The user should then be able to select however many of these people they want.
There should also be a method for saving that group in their contact list, so that a group does not have to be re-created or found in the previously sent list of SMS/emails. This would also allow for easily adding/removing someone from that group as needed.
