For the average Joe, making html tables is such a task. <tr><td> about a zillion times. Yes I realize that anyone putting a table into html should really be using a database, but again for the average joe, that is too much brain damage, and still too hard.
The idea is: Copy excel headers and data into the service, and out pops embeddable html/javascript/whatever code that the person can embed directly on their site. From the user perspective, they can have one place to keep their table data and have an easy way to embed a table into html from excel.
Alternatives: Google Docs embed, zoho creator embed, etc - but these do not integrate directly into the site (ie they cannot inherit css styles from the site) Tableizer - does the conversion of excel cells to html, but does not store the table and data for the user to call at a later date (ie data is static and used once)
It is really similar to the http://myjson.com/ idea, except its for people who don't know what json is.