Ask HN: benefits to trying to define a data standard?

My co-founder and I are working on a new startup (YC rejection, natch) targeted at a specific vertical and helping them with mobile/location services.

The thought crossed my mind of defining/managing a "data standard" for what we're doing. Think something along the lines of MLS data, iCal, rss, etc. We would define the standard, use it in our apps, and other companies would as well. Obviously, the strategy would be to increase exposure and make it easier for mobile apps to integrate or aggregate data.

Any thoughts on this? Good strategy or waste of time? How to approach defining such a "standard"?