Hmm, much to my dismay this does appear to be a Trojan - I can't find any information on it anywhere though. I have found this out:

When you install Limewire it puts a self extracting RAR file into the Temp directory under a seemingly random directory (a key or something), the name of the file is ctywinstaller.exe, it contains the file dlder.exe - which is a Trojan according to NAV, and Housecall.Antivirus.Com.

So.. Now that we have a Trojan (dlder), more mysteriously installed spyware/adware crap (Bargain Buddy, ADP, CyDoor - which doesn't even appear to be used anymore), and a new protocol (ultrapeer) which results in a 10th of the results when searching - there seems to be more and more reasons to NOT use Limewire lately. I wonder, does the version you pay for come with a virus too?