Tim Bray has a very nice summary of open data:

I think any online service can call itself “Open” if it makes, and lives up to, this commitment: Any data that you give us, we’ll let you take away again, without withholding anything, or encoding it in a proprietary format, or claiming any intellectual-property rights whatsoever.

…

For extra credit, a service could also say: We acknowledge your interest in any value-added information we distill from what you give us, and will share it back with you to the extent we can do so while preserving the privacy of others.

So, do we need some sort of Open Service analogue of the Open Source Definition? It couldn’t hurt.

I don’t know if this goes far enough for “open services” — certainly not far enough for the service equivalent of free software. However, it might be nice if “open” meant something substantially different than “free” or “libre” for services, c.f. open source software and free software.

Tim also says:

I suspect that if we can get the basic idea across, then we’re in old-fashioned consumer-advocacy territory; and I suspect that it will only take a small number of painful experiences for consumers to understand the issue at a pretty deep level.

I have noticed, just in the past six months I think, lots of people with no obvious predisposition (e.g., proprietary software background or just regular users) suddenly “getting” the importance of open formats. Promising and pleasantly surprising.