Well, now that Ning has announced that they will be phasing out their free service in favor of premium services, the odds of us migrating there have just dropped dramatically. Since there's no way to import messages from an existing forum into Ning, that makes two key reasons not to move there. Having said that, I'm still a fan of Ning and everything they do, and their premium services are worth the fees. But I currently run SPAN here on my own server so that it is at a net cost of nil. For me to move to any service that would charge me, I would probably have to counteract their fees by having premium ads here, and I am not interested in going that route now.
Posterous was on my radar also but somehow I missed them on the initial pass. Well, I just caught wind that they will be working to make an import for folks to import their Ning blogs. Now, that doesn't directly help us, but with that kind of outreach to a community of folks for whom a premium service is not desired, it gives them bonus points in my book. They are now officially on the option list above.
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