It seems it can use text_wiki syntax, which is a bit different from mediawiki.

This is a normal paragraph.

• list is here
• list is here
  • sub list
  • sub list

And number lists look like

1. line 1
2. line 2

Top level heading

Second level heading

Yet another normal paragraph.

OpenID Momentum is building!

This is a test article.

Heading 3

Heading 4

Block quoted text is Here. How does it look?