An example of interoperability through Twitter - TweetDeck will let you read in both your Facebook and Twitter feeds. And it will let you write to both of them at once.
With open read/write API's like this, web services will be communicating and exchanging data with (multiple) other web services. Ultimately letting web users pull in content from wherever they want, and push out feeds from wherever they want as well.
A couple (very simple) examples to follow on Twitter: @leadnet_org auto-posts the titles from this blog to its Twitter feed. @daily_bible auto-posts a daily Bible verse to its Twitter feed. All through the API.
Software as a Service (SaaS) is becoming Software as a Platform - websites that automatically communicate with other web services on your behalf.
As we listen for opportunities to bless others on Twitter, it will be fun to think of ways that the Twitter API can be used. For example, how might a Twitter app interoperate with your church's presence on Facebook, or with your church's website or podcast directory?

At www.glasgowchurch.com we have integrated the church's twitter account as well as those of our staff into the website. Doing this allows our staff to be more approachable and give congregants insight into the ministerial staff. Currently, we have staff pages set to display recent tweets, recent blog posts and recent messages (recorded sermons/teaching) all on the staff page.
Posted by: Steve Jeantet | April 10, 2009 at 11:37 AM
As CEO of The Bible Society in New Zealand I am always looking for creative ways of encouraging people into the Word of God. I thought I would mention @Bible4U which in just a few weeks has over 3,000 followers. So wonderful to read about @daily_bible!
Rev Mark
Posted by: Mark Brown | April 14, 2009 at 02:34 PM