If you use Windows, I would strongly advise hiding your old limewire on a disc or separate HD, before downloading and opening the new version. It seems to be a bit problematical, and I have yet to see definitive cures for all the problems. this way you can return to your old one if you want.
You can go to
http://www.limewire.com/english/content/download.shtml to download the newest version, and unless you take precautions, this will delete your old one when you install it.
There is talk that 4.8.1 slows down the network ... I have no comment.
MK ultra you will not have to be more careful, but you may become a little more aware of reasons for not doing whatever it is you are suggesting
