I don't particularly care for NOTAMs myself. What's new on the site should be displayed on the main page. I know you're trying to go for the whole "GUI" idea, and it's working great...except for the popup. Maybe a "NEW and IMPROVED!" sign somewhere in that little office-type area? If you must keep the popup, letting the user choose would be the best bet. I don't even really like my site because of the popup, but it's the only way Tripod allows without plastering an ad on my beautiful HTML. Best bet would be to let the user turn it off permanantly, and re-activate it if they wish.
Another alternative could be a scrolling Java Script. An example is on my school's webpage: www.lycoming.edu. On the right is a Java Script telling of all the latest happenings there.
Maybe I'm just sensitive, but popups really are distracting, especially when you're trying to get the user to appreciate and take advantage of your GUI. Just my thoughts on the subject...
-The Jim
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"Those daring young men and
their flying machines..."
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