As with a lot of new technologies the real power comes from when they are used by the masses. Sender Policy Framework or SPF is no longer a new technology and is generally widely used to help preserve email domain reputation for large organisations, but it's as well-known about in the Small to Medium sized business end of the email market. Spammers know this and have started to target domains that do not have valid SPF records as they can most easily be used to spoof and send spam claiming to be from valid companies. Often these types of spoofed email are used in phishing attacks to then harvest more valuable data, so the smaller companies that can adopt the use of SPF the better.