In aug 2008 I switched from blogspot to Posterous. On my blogspot blog I
had about 132 posts. I went to Posterous, and never looked back. Almost
forgetting the blogspot place. Today, Posterous announced they can import your old posts and merge it
into the Posterous blog you want.
And lo & behold, it works, dead-simply!
I now went from 47 Posterous pages to 61, and the timeline goes back to
May 2007. Great work guys!
I wished I new "back then", otherwise I would've kept all my blog posts (since 2000) :-)