Currently the SVN plugin only provides a single SVN revision number for any given URL (ignoring for the moment the fact you can provide multiple URLs in one configuration). Further, ad-hoc tests reveal that this one SVN revision number represents the "last changed revision" for the provided URL.

In certain cases it would be useful to also have access to the "latest" revision as well - ie: the revision of the repository after the most recent checkout or update operation.

I suspect such an enhancement could be made in a non-breaking way as well. For example, perhaps the SVN plugin could provide an option - either globally in the main Jenkins configuration area, or per-job in the SCM configuration section of each job - to have the SVN_REVISION Jenkins property defined by either the last changed revision or the latest revision, as desired. Alternatively, perhaps a new Jenkins property could be introduced, say SVN_LATEST_REVISION, which would contain the appropriate value.

NOTE: I suspect that this enhancement could be used as a workaround to some (but not all) of the workflows being discussed on JENKINS-1241. Also given the fact that either solution I suggested would be non-breaking it could conceivably be implemented and released on all currently supported versions of the plugin.