So my latest cool app is asking Subversion the latest changes over the repository.
It pretty much does this:
svn log #{your_url} --limit #{when_you_d_like_to_stop}
Then, for every revision, it runs a diff:
svn diff #{rev1}:#{rev2}
After playing around for some time with all those commands, my advice is to run svn2rss with Subversion 1.4, as my tests were taking more than 2 minutes to complete.