That’s it. I’ve downloaded and installed the new version twice. On the dmg it shows, in Get Info, as v. 2.0, but after installing it shows as 1.5.4…
What about the program itself? When you launch it, does it have the new icon and does the About box display the correct version? I wouldn’t worry about it too much if it does. I’ve never heard of this happening, but maybe he Finder caches some meta-data like that and it just hasn’t updated.