Just a little trick I learned this weekend. When I first started singing lyrics in-game, I used Poetical, and just the lyrics.
Then, because of confusion in the chat panel, switched to puting a '~' before each stanza.
But at Winterstock, I noticed several bands had a nifty musical note show up before each line in their chat bubble. So I had to ask...
While you are in poetical, while editing the lyrics, before each line, use your keyboard and 12-key pad to enter "Alt + 13" to get a single note, "Alt + 14" for a double note. In Poetical, it will show up as a "?".
It will also show up as a "?" in the chat box, but will place a note symbol in the chat bubble.
You can also do this in the "Say" channel. Just type "Alt + 14" and space, then whatever you wish to sing, and the note symbol will show up in your chat bubble. Again, it will only show a "?" in the actual chat box, so people who aren't seeing the bubbles will just see the "?".
Just thought I'd pass this info on to all who might not know it.
There are many other symbols that you can use here: http://www.alt-codes.net/