Hi,
The long awaited release of subversion "with merge-tracking" has been ready with its first public release candidate. You can find the official announcement here http://svn.haxx.se/dev/archive-2008-04/1120.shtml
In another 6 to 8 weeks we are expecting a GA :) This release includes a lot of feature additions (http://subversion.tigris.org/svn_1.5_releasenotes.html) to subversion.
Try it and report bugs if any, that will help the community :) If you want to know how to use subversion with all those bells and whistles check out http://svnbook.red-bean.com/nightly/en/svn-book.html