We (the mods) screen most new accounts systematically. If a new user posts a blatant ad with a link on their profile at the time they create the account, chances are we’ll catch it (when the volume is high some may slip through, otherwise all get a once-over). Since most of these accounts are created by spambots, not people, that’s the way it usually goes.
But if an account is created one day, and the spam is posted to the profile another day, there’s a good chance we won’t catch that. We’d appreciate a PM alerting us to it. This is much rarer, because it involves a real person. If a real person is behind an account, they may actually participate in threads, too. If someone seems to be participating in the community without an agenda of selling something, then we may just ask them to modify their profile. If a user is clearly just here to sell something, they’re banned outright.
Reporting profile spam is simple. Copy the user’s profile address (e.g. http://www.fluther.com/users/thorninmud/). Click the “Contact” button up by the search window, and paste the address in the “Your feedback” field, along with the word “spam”. We’ll zap it.
Thanks for helping!