Man, I downloaded this yesterday, went to install it today and had to look this thread up to be sure I was getting the wiki right, and there's a new version out!
I've yet to load any ROMs into it to test it out, but great job. I definitely like the new toolbar.
On the note of making it look "more professional" (keeping in mind I have absolutely zero programming knowledge so this may be far more work than it would ever be worth) perhaps add a status bar at the bottom of the screen. Something to tell you what system/emulator you have selected, what version of ROMbrary you're running, what ROM you've selected, etc....Just anything that you may want a quick reference to using the program.
Here's a screenshot of the one Azureus has to offer:
http://img130.imageshack.us/img130/228/untitled8zd.jpg
Also, adding cascading menus at the top - File Edit View Tools - would add a level of professionalism and familiarity I think. I don't know what you'd fit into those menus as it's a pretty simple program...Just a bit of input, hope it helps at all, and thanks for the awesome program!