I've also just been experiencing the Limewire "unexpectedly quit" problem - but I've fixed it!
The problem was caused when I turned off all of my fonts in font book (i was trying to fix a font conflict).
Without the fonts loaded, Java does the "unexpectedly quit" act. And because Limewire is a Java app, it also quits.
By just turning my fonts back on Java and Limewire are working again.
So check all your system fonts are loaded - this could be a simple solution.

Cheers,
deano