This PDF gives a good view of Sigma on a larger scale.
http://www.sigmatv.com/nqcontent.cfm?a_id=1213
Be Agile in your Company Vision from http://www.sitepoint.com/article/application-fluff-hot-air/
In fact, there's no need to even have a vision. If you've executed your promotion strategy correctly, people won't care what your application does -- they'll be so dazzled by the flashy site and use of cutting-edge technologies that they'll forget that they've never actually used the thing.
Not having a vision makes you more adaptable. If you want to take your application in a different direction, you'll find it much easier to do so if you haven't committed yourself to any particular path.
SOAP and RPC CMS engines
http://www.squiz.co.uk/mysource_matrix/mysource_matrix
http://www.xmlrpc.com/manilaRpcSpec
http://robertmaldon.blogspot.com/2008/05/build-your-own-java-cms.html
For some overwhelming research