I've set up my iCloud account on my iPhone4 running iOS5 and have mail enabled, however, it is not showing up in the mail application itself. Here are some screen shots. Any suggestions?
When you go to your mail box there is a tab in the left upper corner that says inbox. Click on it and it will take you into a screen with all available inboxes. Click on "all inboxes" and it will show both email accounts in one.