Definitely. Admins should be able to make the feature unavailable and students should also be able to choose not to display their birthday. But the birthday feature is really a part of a bigger picture that Ive been rotating in my head
The act of online participation in itself is a great learning opportunity this is especially true in the elementary and high school environments. Since many of my students have limited computer skills, their participation not only improves their language skills (I run an online literacy program) but its also a great way to beef up their computer skills (typing, uploading/downloading, online discussions, email, Internet surfing the list is long).
As with all of us, Im excited about all the Moodle functionality that is constantly being added/upgraded; proposed upgrades to the gradebook (Im particularly excited about this one), assignments, and other modules, are providing online educators with some great tools. Im also increasingly excited about the community-building potential that Moodle has to offer. My students visit the Moodle site from home! Why? Well, not for the assignments, I can tell you that
(they have classroom time for that). They come to visit the discussion areas and check out other students profiles in short, they come to visit the community.
As Moodle grows in functionality, I hope the community aspect grows along with it. The birthday feature may (or may not) be an example of one such community-building idea, but Im just advocating more community-building features in general. 
Fernando
). Anyway, just thought Id throw it out there. 