When did you notice this? What OS do you have on your computer?
Also, go to your applications folder and check out the .incs file for iTunes.
(That is, control-click on iTunes, show package contents, go to contents, resources, and open up the file called iTunes.incs). Is it the same?
Also, try removing the iTunes 1 logo depicted in the attachment and move your iTunes 3 logo to the Dock. The logo may only need to be refreshed.