While I can easily find the binaries for the latest version of subversion (1.6) I can't find the binaries for Ubuntu (or Debian).
The download page at tigris.org suggest to use the command:
apt-get install subversion
but as you can experience this will install up to the version 1.5.4 (at the time of writing May 6, 2009).
This isn't a nice thing because many working copies that I share with Windows are automatically updated to 1.6 by TortoiseSVN.
You can find a debian package for subversion 1.6 in the experimental repositories from debian at http://packages.debian.org/experimental/subversion.
Having said that you would probably be alright working with version 1.5.4 from the ubuntu repositories, if the svn server you are using isn't running 1.6 you won't be able to use any of the new features in the client anyway.
If I was you I would first try to use the version in the repositories before installing it from a third party as you may find that it does work for you and it will make your life easier when it comes to updating subversion in the long run.
You don't need the 1.6 version to work with your Windows working copies. SVN is clever enough to recognise the features provided by clients, and only allow those features through - so your 1.5.4 client can connect to your 1.6 server without any problem; as can your Windows 1.6 client.
The only time you'll have problems here is if you're using 2 clients with a single working copy - ie your Windows and Linux clients both commit and update a single, shared directory. Such an arrangement is a bad idea anyway, you'll have all kinds of problems even without counting EOL differences. If you have such a situation, checkout a new WC, so you have one for Linux and another for Windows.
Solved! Here the solution.
From the CollabNet download page download the binaries for Red Hat. Then use alien for installing it, for example:
$ sudo apt-get install alien
$ sudo alien CollabNetSubversion-client-1.6.2-1.i386.rpm
$ sudo dpkg -i collabnetsubversion-client_1.6.2-2_i386.deb
Beware that the command is installed under /opt/CollabNet_Subversion/bin/svn not in /usr/bin/svn. So after that simply put this line in your .bashrc:
export PATH="/opt/CollabNet_Subversion/bin:$PATH"
Here is an APT repository with Subversion 1.6 binary packages for Ubuntu 8.04 through 9.10: https://launchpad.net/~anders-kaseorg/+archive/subversion-1.6
I solved it with these repositories:
deb http://ppa.launchpad.net/anders-kaseorg/subversion-1.6/ubuntu intrepid main
deb-src http://ppa.launchpad.net/anders-kaseorg/subversion-1.6/ubuntu intrepid main
You can find certified binaries here, now: http://www.wandisco.com/subversion/os/downloads?type=ubuntu910
The script will setup a repository for you, so you will keep on getting updates.
Add these two lines to your /etc/apt/sources.list:
deb http://ppa.launchpad.net/anders-kaseorg/subversion-1.6/ubuntu hardy main
deb-src http://ppa.launchpad.net/anders-kaseorg/subversion-1.6/ubuntu hardy main
Get Anders key:
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 413576CB
Update:
sudo apt-get update
Upgrade or Install:
sudo apt-get upgrade
sudo apt-get install subversion
(Via GVS)