Just realized yesterday's blog post was my 2,000th post since 2003!
That's primarily a few years on Blogspot before moving to WordPress, and imports from a few side projects and experiments with other platforms over the years, like Vox and Posterous.
I don't think it includes Google+, but I can't remember if they offered an export option before killing it?
It also doesn't include LiveJournal (which somehow still lives on!), nor my time on Compuserve or Geocities, which is lost forever.