Just downloaded Montezuma, and have to say - overall awesome and totally usable out of the box.
The best bits so far:
- clean, minimalist design
- header doesn't take over the above-the-fold area, swamping content
- sidebar is sized appropriately to support advertising
- Great support for Menus, Widgets, Galleries, Comments, and other niceties
In fact - only downside I've seen so far is the breadcrumbs render a bit oddly in Chrome (flawless in Safari & Firefox)