How does Atahualpa distinguish static pages?

I am writing a simple e-commerce plugin (for Google checkout) using a WP3.1RC-1 custom post type to describe each 'product'.

I want these post types to be treated by default, more like a static page than a blog post, not just in Atahualpa but in general in any theme so I'm interested to know:

1) How Atahualpa (and themes in general) determine how to display a post as a static page (as opposed to a post)?
2) Is there a way, which is not theme dependent, to cause my custom post type to be treated like a static page when formatted?

Thanks

Mark