We typically go with a different approach using the "Coming Soon" theory.

For example, for the launch of our new site, since it will no longer be catering to only software, but also design, media, and audio/visual entertainment services...

We're going with a contest, built around the date of launch. As such, we're using a very detailed flash animated countdown clock, and providing clues to win the contest, throughout the timeframe.

This gets people to come back over and over to get the next clue, gives them something to look forward to, and lets them know that something is "coming soon".