[updated 25.08.]
If you sometimes get a little bit nervous about the particular behaviour of CVS and it's features like reanaming or directories in general, then Subversion [1] could be your cure. One amazing feature is the binary diffing algorithm it uses...

Goal of the Subversion project is to build a revision control system that is a compelling replacement for CVS in the open source community. Interims release 0.28 [2] is available since today, features planned for 1.0 include:

• Most current CVS features : Subversion is meant to be a better CVS, so it will have most of CVS's features, with as many as possible in the 1.0 release.
• Directories, renames, and file meta-data are versioned : lack of these features is one of the most common omplaints against CVS
• commits are truly atomic
• Apache serving via WebDAV/DeltaV
• Branching and tagging are cheap (constant time) operations
• Natively client/server, layered library design
• Client/server protocol sends diffs in both directions
• Costs are proportional to change size, not data size
• Efficient handling of binary files : subversion is equally efficient on binary as on text files, because it uses a binary diffing algorithm to transmit and store successive revisions.
• Parseable output : all output of the Subversion command-line client is carefully designed to be both human readable and automatically parseable; scriptability is a high priority.

These features look pretty interesting and after 1.0 [3] there shall be even more:

• Support for symbolic links
• "svn blame" (cvs annotate)
• Better merge support - improved support for selective merges
• Internationalization
• Progressive multi-lingual support

If you are using Eclipse [4] then this Subversion Eclipse plugin [5] or Plugin for Eclipse - Svn4Eclipse [6] will be your thing. But there are lots of other plugins for Visual Studio, IDEA, Emacs etc. available (check the bottom of this post).

These aspects could make your software configuration management (SCM) even better, but I fear that adoption of Subversion against CVS requires time and budget and that is good because already Steve McConnel [7] already pointed out in his amazing 36 classic mistakes for failing software projects the "silver bullet" syndrom kills a project more often than a not so optimal SCM... Silver bullet syndrom: nerds think they can make up lost time in the project by adding new and better tools - really dumb-asses (I know one) think that even for adding a bulk more people ...

More great tools/plugins and articles:

• Plugin for Windows Explorer - TortoiseSVN [8] - TortoiseSVN is TortoiseCVS for Subversion. Enables Subversion commands directly in Windows explorer.
• Gui: Jsvn [9] - Project page with Information, Sources, Bugtracking for the GUI implemented in Java/Swing. It is based on the command line interface.
• Gui: RapidSVN [10] - Project page for the GUI. Information and sources for the cross-platform GUI front-end for the Subversion revision system written in C++ using the wxWindows framework. This project also includes a general Subversion client C++ API.
• Gui: Supervision [11] - Cross Platform Java/Swing Gui. It is based on the command line interface.
• Gui: Svn-up and plugin for Idea [12] - Cross Platform GUI in Java/Swing based on the Subversion HL-API for Java. It offers support for management tasks and convenience functions for everyday work.
• Plugin as General SCC Provider - Subway [13] - News, Downlaod and info about Subway. It integrates Visual Studio .NET with a revision control system with Subversion.
• Plugin for Eclipse - Subclipse [14] - Enables Suvbersion support in the Eclipse IDE.
• Plugin for Eclipse - Svn4Eclipse [15] - It's aimed at being a replacement for the CVS plugin.
• Plugin for Emacs - psvn.el [16] - The page has the sources and information on the module.
• Plugin for .Net - ankhsvn [17] - The aim of this project is to provide integration for SVN into the Visual Studio .NET IDE.
• Article on Multiuser Subversion Setup [18] - Demonstrates how to use Subversion for multiuser, distributed projects.
• Article on Single-User Subversion [19] - Introduces Subversion and explains how to use it for personal projects.

And Subversion: The Definitive Guide [20] is under development and open available, is going to be published by O'Reilly and Associates later in 2003. Maybe grab a copy and give the author feedback - I like this book-beta work.