It may come as a great shock, but most librarians aren't actually web designers; they are in fact librarians. Now that's not to say that there aren't many librarians who have some html, Java, design, or other skills, but for all but a few places their primary job is something other than minding their library's website AND THEN on top of that job they do work with their library's web pages. And, as anyone can tell you who has ever had a personal web page, websites (especially ones as extensive as the LoC) can be more than a full time job.

And it may also come as a surprise that libraries (particularly those who get all or most of their funds from tax dollars) don't have huge budgets. And those limited budgets have to be divided between paying reference staff, doing conservation work, scanning materials, cataloging, keeping the building in repair, etc., etc. - making websites one among many expenses. And web redesigns (particularly if you can't do them inhouse) aren't cheap, never mind the fact that you can't just redesign your site once and then leave it alone for ten years. You may have to lay out a significant expense frequently as times (and technologies) change. It doesn't take any great leap of logic to say that, given limited time, funds and staff, it might be a good idea to allow the librarians to do what they do best while taking advantage of the Flickr folks doing what they do best.

As for the tags given to the photographs, it's long been known in libraries that the way librarians catalog images is not how people search for them. Librarians index things like photographer, location, time period, the names of the people in the image, etc. - things that you need to know to understand the historical context. But many folks looking for images aren't looking for a specific person or place, they don't care if it's "Sue Bob, Aug. 1943" because they're looking for a cool photo of a "woman" with "red" lipstick wearing a "blouse." Now, given the volume of images that most special collections/university libraries/etc. have, there is no way that anyone would ever have the time to index ALL images to that level of detail. Maybe the public can help with that? I don't know, I'm not completely sold myself on that part of the partnership. But since nothing like this has ever been done, we've had no way to know what might happen or how useful it might/might not be. It's wonderful that the LoC is taking the risk there since there are many other libraries all over the country who will be watching the experiment closely to see what happens.

If my answers don't suit you, or if you want more information about these issues, then my suggestion is that you call the university or special collections library near you. Because my guess is that most of these questions could have been answered in a 10 minute phone call with any librarian. If you'll tell me where you're located I'm sure I could suggest a few. Or if you'd rather not do that, then I'd encourage you to write these questions in the comments of the LoC blog. I'm sure that, much like with the folks who are asking questions on Flickr, the staff of the Library of Congress would be more than happy to answer your questions directly. After all, answering questions is at the core of what librarians do.