Pluses
iFrames are very simple to use. They work almost like a frame does, but can be more customizable.

Negatives
You can only view iFrames with newer versions of IE, Opera (sometimes), and newer versions of Netscape.


Here's a review of Iframes versus text overflowing for scrolling:

http://9rules.com/whitespace/design/...s_overflow.php

About the only reason given for not using iframes would be browser compatibility... I guess.

Reverend should be able to chime in more about this issue. He knows a bit on this topic. I am sure some other TZers do as well.