Are there any plans to add the icon back in? I don't understand why it
disappeared and it seems (from a brief web trawl) that I am far from the only
one.

It was a big negative for me in terms of my reaction to Outlook 2007 and one
of the first things I noticed, instead of looking at great features such as
the search. Anecdotally, when I mentioned the missing icon to my colleagues,
they all reacted negatively and some have refused to upgrade because of this.
It may appear to be trivial, but clearly it is not.

Using colour formatting is fine if you don't already use colour formatting,
but I do. The use of an on-screen icon was simple and clear - so why change
it?