] The company is strongly urging e-mail providers and
] Internet service providers (ISPs) to publish Sender
] Policy Framework (SPF) records that identify their e-mail
] servers in the domain name system (DNS) by mid-September.
] Microsoft will begin matching the source of inbound
] e-mail to the Internet Protocol (IP) addresses of e-mail
] servers listed in that sending domain's SPF record by
] Oct. 1. Messages that fail the check will not be
] rejected, but will be further scrutinized and filtered,
] said Craig Spiezle, director of Microsoft's Safety
] Technology and Strategy Group.

Microsoft is planning on enforcing SPF. Fortunately they aren't going to outright drop non-SPF emails, but it remains to be seen if MemeStreams email will go through to hotmail accounts after this change. SPF breaks systems like MemeStreams that send out emails on someone else's behalf. There is a workaround, but it is hacky to the point of being considered harmful, and I can't easily employ it because outbound email from MemeStreams comes from the webserver and not the mail server. In any event, if you notice that your memestreams messages aren't getting through as this moves forward please let me know. Its going to be a hell of a lot of work to address this and I don't want to do it until it becomes a real concern and not just theoretical.

InfoWorld: Microsoft to break MemeStreams