Oddly enough I was planning on starting this post sometime soon anyway, after a lousy and frustrating search experience last week. When I logged in on Monday it was obvious there were some bigger problems so I decided to wait a bit. That said, it seems like there are probably more folks thinking and posting about what (doesn't) work right about now and the chowhound engineers are obviously working hard to respond. So...
-I see search results are now defaulting to a most-recent first order. Great improvement.
-knowing what you're searching. Before a search from a board searched that board first with the option to expand. That made sense. (update: I see you've already mostly fixed this--thanks!)
-labelling on search results. An example of what I'm talking about: what the heck are the "filters" (and I don't mean that literally, I'm familiar with the concept of filters)? Filter by "all" is contradictory. Filter by topic makes no sense--there is no section called topics so it isn't clear what is and is not included
-whole word searching--if I search for "eat" I don't want to find "great". Stemming (searching for alternate word endings) might be ok, perhaps as an advanced search option.
Ideal search features (in advanced search at least)
-preview of where your term appears in the initial list of results (a la Google) so you have a better chance of choosing a relevant result
-ability to use boolean logic, nest terms, and to search within results (yes, I am a librarian, but I know I'm not the only one who uses this stuff)
-ability to sort results (or you can call it filter if you want) by board, author, date, relevance, etc. as desired
I'll probably think of some more, but what search features are others pining for?