This one is pretty simple:
I am using Outlook 2010 in "Conversation View" which is great except for the fact that Sent Items do not show up in this view.
When using the beta version of Outlook 2010, my sent items did show up in this view. It required me to click on the "dropdown" arrow to the left of the conversation an extra time, but once I did, I could see my own sent email along with the rest of the messages in the conversation.
The retail version of Outlook 2010 is not doing this, and I have spent quite some time digging through all of the options and I haven't found any way to enable this.
I do know about the cheesy solutions such as setting up a rule to BCC yourself on all of your email so that it shows up in your inbox, but this is not what I would like to do; there is (or was, in the beta) a way to natively support this; I just need to figure out how.
I am on Exchange if that matters.