I just converted my blog from Wordpress to Jekyll. The process was fairly straightforward, although it took a lot of reading, and viewing other people's example sites.
One issue that took a while for me to figure out, was a small typo.
In _layouts/post.html, I was using the following syntax to include my post content:
{% raw %}{{ page.content }}{% endraw %}
As I was converting my posts to use markdown syntax, the posts weren't "markifying". It turns out, all I needed to do was use this syntax:
{% raw %}{{ content }}{% endraw %}