I did the same research some months ago and didn't find "the" solution or answer to this question.
Linkdump from my bookmarks to this topic:
Discussion: http://blog.sonoasystems.com/detail/one_size_doesnt_fit_all_... http://stackoverflow.com/questions/389169/best-practices-for... http://stackoverflow.com/questions/2024600/rest-api-versioni... http://stackoverflow.com/questions/972226/how-to-version-res... http://stackoverflow.com/questions/278686/versioning-restful... http://stackoverflow.com/questions/1679322/web-services-api-... http://stackoverflow.com/questions/2101566/what-are-your-web... http://barelyenough.org/blog/2008/05/versioning-rest-web-ser...
Examples: http://docs.amazonwebservices.com/AWSEC2/latest/APIReference... http://atlas.resources.ca.gov/ArcGIS/SDK/REST/versioning.htm... http://groups.google.com/group/twitter-api-announce/browse_t...
Hope this helps a little bit.