I tried importing all of my old tumblr posts using the Jekyll-Import plugin.
{% highlight ruby %}
$ ruby -rubygems -e 'require "jekyll-import";
JekyllImport::Importers::Tumblr.run({
"url" => "http://lramage94.tumblr.com",
"format" => "md", # or "html"
"grab_images" => true, # whether to download images as well.
"add_highlights" => true, # whether to wrap code blocks (indented 4 spaces) in a Liquid "highlight" tag
"rewrite_urls" => true # whether to write pages that redirect from the old Tumblr paths to the new Jekyll paths
})'
{% endhighlight %}
It didn't work too well. I had a few of my images but none of my links to external resources were imported. I guess it's better than nothing.
After it imported I used perl to replace the layout from post to my own layout type,
{% highlight perl %}
$ perl -pe "s/tumblr/post/g" _posts/tumblr/*.md
{% endhighlight %}
Also as you can probably tell, syntax highlighting does not seem to be working?