Yesterday was a major code freeze date at my day job.
In general, code freeze doesn't mean an awful lot to me; I'm a big fan of agile methods, in particular Continuous Integration (I consider Martin Fowler's essay on the subject to be the single most important thing you can possibly learn about how to successfully run a software development effort).
However, I've been at places where code freeze never occurred. Nobody seemed to care about schedules, or about whether software projects were ever completed or not; work just carried along, and sometimes got released, leading to all sorts of programmer gallows humor (example: "we have a constant here: code freeze is always 2 weeks away").
Now, schedules aren't everything, and code freeze isn't all that important, but time does matter, and deadlines do concentrate the mind, and software should be released, and so I'm pleased that we made our code freeze date, and I'm pleased with the work that was completed and submitted in this cycle, and I'm pleased that, as the deadline approached, the entire organization has become more serious and more vigilant about firming up and solidifying the software in preparation for the upcoming release. As Jeff Atwood points out: real developers ship product.
We've put a huge amount of hard work into the release, and I'm very excited about the idea that it will soon be out for customers to start working with. Get ready for lots of fun new version management functionality to arrive soon!