Subversion 1.5 has arrived: http://blogs.open.collab.net/svn/2008/06/subversion-150.html.
TortoiseSVN 1.5 is not yet released, but has reached RC3 status. I tried it and must admit there are quite some improvements to note. There is also a beta of VisualSVN 1.5 (also for the server).
You can get the binaries, and read more about the new features here:
- Subversion 1.5: http://www.collab.net/products/subversion/subversion15.html
- TortoiseSVN 1.5 RC3: http://tortoisesvn.net/node/328
- VisualSVN 1.5 beta (client+server): http://www.visualsvn.com/beta/
Edit: In the mean time, both TortoiseSVN and VisualSVN have released 1.5 final
