To answer the obvious question first. yes I did do a battery pull.
Now the application is the gmail app. I see it installed when I look at the application list, but I can't for the life of me find a way to have the phone display the icon. Also of note is that in the application list, the gmail app is in bold while the other apps are not.
I remember reading some information on what this meant, but tried a new search and am unable to find the info again.