I'd like to stylize some words into a button-esque image per a branding strategy, and then have their standard-text versions be replaced with image site-wide.

Is it possible to replace a word with a presized image? If not, how hard would it be to add this support?

Or would the Search and Replace Scanner module be a better option (http://drupal.org/project/scanner)?

I've refereneced another issue regarding inserting HTML: http://drupal.org/node/262590