When Mac OS X Leopard first came out (I think it has been almost a year now), the menu bar was a pretty big controversy because there were conflicting opinions on its aesthetic beauty. Personally, I like it just fine either way. Mainly I prefer the transparent/translucent bar because it has more color to it.
Just in case you do not know what I’m talking about, here are some screenshots.
Originally, there was no option to turn off the transparency (there probably was a hidden command you could use in terminal to disable it) until Apple finally came through and added the option in an update because of all the translucent bar dissers.