I wanted to echo Orin's recommendation of Rick Hasen's item on the FEC and blogs. Rick is a leading election law scholar, and a very thoughtful fellow, as well as the leading election law blogger. He tends to be more pro-regulation than I am, but I find his work to be much worth reading.
One small disagreement I have with Rick's piece: He writes that "As a matter of policy, bona fide on-line journals and political bloggers such as Hugh Hewitt, Andrew Sullivan, or Joshua Marshall, should be treated the same as the New York Times and David Brooks" (I agree so far) but then says that "Online corporate-owned journals like Salon.com, however, do not appear to fall within the literal ambit of [the] 'media exemption' [to restrictions on corporate speech about candidates] nor do any blogs that are owned by corporations, because the exemption on its face applies only to broadcasts, newspapers, and periodicals."
I think that, literally, blogs are periodicals. They are published fairly regularly, rather than intermittently, and they reach more than a few people; that makes them "periodical publication[s]." (The relevant exemption comes in 2 U.S.C. sec. 431(9)(B), "The term 'expenditure' does not include--(i) any news story, commentary, or editorial distributed through the facilities of any broadcasting station, newspaper, magazine, or other periodical publication . . . .")
It would be good to clarify FECA to make clear that Weblogs and online magazines are exempted. But I think that, properly -- even literally -- interpreted, "other periodical publication" already includes blogs (except perhaps ones that publish intermittently and very rarely).
(Note that some dictionaries define "periodical" as meaning less often than daily, but that's not the majority definition, and it's not apt in this context, since "other periodical publication" shortly following "newspaper" suggests that newspapers, many of which are daily, are periodicals, and therefore that "periodical" includes daily publications. Also, one can argue that "periodical" requires a fixed period between items, such as roughly 24 hours or 7 days, and that therefore blogs that sometimes have posts 5 minutes apart and sometimes 15 hours apart don't qualify. But I don't think that periodical requires such fixed intervals -- publishing at least once a day should be as periodical as publishing exactly once a day at a fixed time -- nor would it make much sense.)