It's not exactly easy to set up an SPF record, especially from within a shared server environment. WHM/CPanel et. al. could make it as easy as pushing a button, or entering a record automatically when a domain is created. Not something cryptic and geeky like "define an SPF record" but plain words like "Prevent Spam Sent from This Domain". So maybe the people to talk to are the ISPs and the server control panel developers.
Microsoft has a nifty little Wizard,
microsoft.com/mscorp/safety/content
...
but here again you only get the record itself and no clue what to do with it other than MS's usual advice to "give it to your network administrator".
I'm saying if you want to encourage adoption of a given technology, you've got to bring it to attention in layman's language and then make it easy to implement in layman's language. I'm a life-long geek, and still don't quite understand DNS because I can't know everything.