Keylogging software- new wave of security? or just an invasion of privacy

Keystroke logging software has been around for nearly as long as the internet has but what invoked the creation of such a software? Frankly, is it a new wave of security for individuals to conform to or rather a Constitutionally imposed invasion of privacy?
Keystroke logging software began as a virus in which hackers would deliver such a software to unsuspecting victims to obtain crucial personal information such as social security numbers, credit card numbers, and account information. What it does is it secretly runs on a computer without the impending victim's knowledge, then records all keyboard activity and stores all information for the perpetrator to obtain.
Keystroke logging software began to take notice to private citizens as well as government agencies as a useful tool to use around the home and office. What emerged, was the creation of new found software which allowed private citizens to purchase to install on their own computers or where desired. In 2000, the Federal Bureau of Investigations (FBI) first implemented the use of keystroke logging software on the computer of Nicodemo Scarfo. Again in 2007, ecstasy manufacturers, Mark Forrester and Dennis Alba, had become the victims to the FBI's keystroke logging software. Is that permissible? Should there be an exception for such extreme cases?
According to the 9th District Court of Appeals, the federal government did not violate Scarfo’s Fourth Amendment rights and have right to proceed with such acts as long as the information they are obtaining are related to the warrant.
Now if the courts view using keylogging software as outside the meaning of the Fourth Amendment then does that mean police departments around the country will begin implementing the procedure into their daily patrol routines? Are we now fully vulnerable to having our right to privacy invaded? If the courts have established that keystroke logging software is permissible as long as it pertains to warrants, then installing cameras or other technological items within a dwelling may be around the corner as well. One issue that must be imposed is will the courts approve of law enforcement using such software to develop probable cause?


http://news.cnet.com/8301-10784_3-9741357-7.html
http://forums.techjunkie.com/3241_userID=1245235063/T=14353-32/Keystroke_logging