My favorite feature in Windows Mail in Windows Vista beta 1 is word wheel search.
There is a textbox in the upper right corner of Windows Mail. As a user types text, the list of messages will only show emails that contain that text. This will work when searching subjects, TO / CC / FROM lines, or the body of the message.
I have become addicted to this feature because it’s the best way to search for an email. It doesn’t require hitting enter and it searches within a second or two.
CTRL-E will move the cursor to the word wheel so users can search quickly without switching to use the mouse. The escape key (ESC) will clear the text to show all messages. If the word wheel is empty, the escape key will return the previous search text.
Searching for text in the body is possible shortly after the body is downloaded.