Is is possible to have a defined view that shows unread mail AND all
mail (read and unread) that was recieved today?

What you really want to leverage is the search folders, which are
avaialable only in Outlook 2003. To get what you want, do the
following:

1. Ensure the navigation pane is showing by going to view -> navigation pane
2. Right click on search folders. Choose new search folder...
3. Scroll to the bottom and highlight "create a custom search folder"
4. Click the choose button
5. In the name box type in "Today's Email"
6. Click on the criteria button
7. Under the time drop down choose received
8. Choose today in the other drop down
9. Click OK and OK

Now highlight the custom search folder you just created. You will see
all messages from today in all folders, including your sent items. If
you want to see only items in the inbox the custom search fodler can
be modified to do so. Here's how:

1. Right click on the Today's Email folder and choose Customize this search folder
2. Click the criteria button
3. Click the advanced tab
4 Click the field drop down
5. Choose all mail fields -> In folder
6. Under condition choose is (exactly)
7. In the value box type "Inbox"

That's it.

I don't think that will do what i want.  
What you suggest will only show the emails i have recieved that day. 
I want to show this AND any email that has unread status (independant
of when it was received).
Thanks.