Three years is a long time on the Internet, and I wouldn't be surprised to see a lot of consolidation among ISPs in that period. Whether that will be good or bad for users is yet to be seen. Firefly's whole point is only to share recommendations among the sites that use it, and they say they would never release your e-mail name to junk mail lists. You're more likely to get on one of those lists if you use your e-mail address in Usenet groups and chats. Public directories, such as Four11, are another fertile ground for spammers to find their prey.
Cookies seem to get a really bad rap.
What's good about cookies is that they can store your preferences when you visit a site, so that you don't have to reenter data every time you visit. That allows for sites that are more easily customized to what you want. This makes it effectively impossible to record a user's personal information or preferences, whether that information is a credit card number and shipping address or favorite sports teams. Cookies offer a mechanism for keeping track of this information on the user's machine, and individual cookies are supposed to be accessible only to the site that created them. But like any technology that collects personal information, it has a potential for misuse by the unscrupulous.