It's easy to do in Wordpress, but in Community Server, I have to edit SQL to change the author of a post. Admittedly, I've not used TC 5 extensively yet, I still have 2008.5 SP2, but I've not read that this feature has been implemented, even though it sounds easy enough to achieve.
It means that admins could write blog posts for others who either aren't technically skilled enough, or simply don't have the time. Impesonation goes some way to helping, but if you prefer to use a blog application like Live Writer, you can't impersonate.
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