Microsoft’s CodePlex site is a customized Microsoft Team System hybrid for hosting and developing open source software projects. After using CodePlex for a while, I have to say I’m really impressed. Microsoft has come up with a fantastic, easy to use development 
environment and opened it up to the open source community. I hadn’t used their Team System product prior to this, but after using CodePlex I don’t think I’d want to go back to using anything else.
CodePlex is a very feature-rich platform for development. I love the tools they give you to work with: 
a wiki, the ability to aggregate news feeds, discussion forums, issue tracking, automatic zipping of source code, planned releases, a release repository, a project member directory, and license information. These features by themselves aren’t that impressive–some of them are rather bare-bones implementations such as the project directory which is just a list of user names, and their feed support which doesn’t support ATOM (as M. David Peterson recently pointed out and fixed by himself with his XML-foo.) However, put them together in one place and you have a pretty formidable system. Put VERY tight Visual Studio integration on top of that (still my favorite dev environment), and you can be up and running with a full-featured, easy to use development project with full documentation integration in a matter of minutes. Compared to the 
new Google Code project hosting, it practically looks like a wealth of features. I’d say Microsoft handily beat Google on this round of releases, although it probably helps that Microsoft has years of experience creating and supporting development environments to lean on.
If you use Visual Studio, the integration with CodePlex is just really sweet. I remember the old days of trying to get SourceSafe working with Visual Studio, and even when you finally got everything configured and up and running it would just stop working at random times for no apparent reason. 
SVN integration is just as bad from my personal experience. CodePlex, however (and I would assume Team System on which the VS integration is built), just WORKS, and works well. The issues from the CodePlex site flow into the work item list in Visual Studio and when you mark something off as complete or check in code with comments those show up in CodePlex seamlessly. I already don’t want to go back to working without it.
Right now Microsoft is accepting new projects into CodePlex on a case-by-case basis, which is definitely the way to go for a new system of this type. If it got overloaded and went down at all it would leave a pretty bad taste in developer’s mouths–when I have some code to crank out, nothing had better get in the way. Which is one of the main reasons I’m starting to love CodePlex–it doesn’t get in the way, it just works. And it gives me all the tools I need to just work myself.
If Microsoft is smart they’ll release a non-open source version of CodePlex for commercial products for small dev shops, because I for one would sign up for it TODAY. Instant hosted development environments of this type are the way of the future.
