The spec isn't explicit about what formatting the description can contain.
The assumption is probably that it's plain text, but it may be worth being very explicit about it (e.g. that LF is a visible line break and HTML tags and entities have no special meaning and are to be displayed literally).
In RSS 2.0 this hasn't been clearly specified and titles and descriptions ended up being an ugly hybrid of plaintext and HTML that requires consumers to "sanitize" those strings and sometimes results in malformed content.
-- regards, Kornel
