All of the search forms on the site fail to work in the expected way: type query, hit enter.  Instead, one has to click the "go" or "submit" button in order to get results.  To make matters worse: if you DO hit enter, the page reloads but without filtering or executing the search, so it appears that the search is just broken until someone tells you it worked for them and you start trying different ways of submitting the form.

Yup, confirmed (although I didn't actually have the same expectation you did - it does work in the way you state). That's unfortunately the way the Web site's software works - it doesn't insert the Javascript necessary to pick up the Enter keystroke, and since the Search link is a LINK, not a BUTTON, your browser doesn't "see" it as a target. So your browser takes Enter to be "reload." I'm not sure how much control I have over that - I'll fuss with it and see.

It doesn't take javascript. Hitting Enter "submits" the form ... the problem is that the form itself doesn't search when it's submitted.

Actually, having done a very thorough trace with some debug code quite late last night, I can assure you that hitting Enter does not, in fact, submit the form. I've also been in touch with the developer of that module who assures me that they're aware of the problem and that pressing Enter doesn't submit the search form. They're researching workarounds.

I hate to mention this, but I cannot get search to work no matter what I do - I click the little hourglass icon, and I get the same results as if I hit enter.

"the page reloads but without filtering or executing the search, so it appears that the search is just broken"

We will check it out asap, thanks for the report.

Fixed! It was a missing index.