Limewire is not dangerous. Limewire does not come bundled with spyware (if obtained from click here). Limewire in itself is not illegal.
Provided that some care is taken in the choice of files to download (avoid exe/zip files etc..) and provided that a PC is equipped with adequate AV and ASW progs., there is only a very minimal security risk.
I know this because I used Limewire for many years, not because I read it in an article somewhere! Now I use Frostwire (essentially the same source code as Limewire) click here partly because of click here.
For the real facts on Gnutella Network clients, visit the good folk at click here.