yes, but you have to take into consideration that unless you've put a lot of clever JS together to protect against it, you will probably lose the functionality of the "Back" button/bookmarks/browser history.
this means less page views, in the traditional sense.
i think AJAX is cool, but if you're doing it just to do it, you probably should avoid it.
by "flashy" i meant dynamic content, without a page load. this can be cool and also annoying.