Getting proper credit in a game matters. As a professional developer, a large part of your ability to get hired is the list of projects you've previously worked on; if you aren't in the credits, it becomes much harder for future employers to verify.
Many professional developers don't realize how important it is (until they get burned by it). This makes it rather important to at least mention it briefly to game development students, so that they're aware before getting burned.
As of just recently, the IGDA Credit Standards Committee released a beta version of a standards document. Several very large teams are putting this through its paces on real projects, to see where the problems are. (The document itself can be found at the link above.)
For those of you teaching a class in game development, especially one such as a "capstone" that involves students working on teams to make working games, consider making your students comply with the credit standards. If you have a student working in the role of Producer (or else Project Lead), you can make that an assignment for the student to ensure proper crediting of everyone on the team.
If you do so, be sure to let the Credit Standards Committee know how it goes. I don't think they've got anyone testing out the standards on a small-team project yet, and it'd be nice to know if the standards scale down properly.