Tableau 7 won't include 3-digit zip code boundaries or points. It's on the list of things we may add at some point, but there's no particular date we are promising it.
Thank you for the rapid response.
I understand that it will not be built into the product, but is there an easy way for me to accomplish this short of building a polygon table?
No. Tableau 7 does not include support for custom filled maps - you still have to use polygon tables.