hrm, when I try this, pressing backspace takes me back to the search page, with the livesearch form and the advanced search link.  clicking advanced search link goes to a clean adv search form. Is this another IE6 one?

Hmmm, I can't repeat this now either.  I would have found this bug either in FF or IE7.
Code may have changed?

I've managed to find a similar problem (not the same as my original report):

From the Search page, press Search button without entering any text.
"No Search Results" is displayed within the search page.
Press Advanced Search.
"No Search Results" remains displayed at the top of the Advanced Search form.

that last bit is the same cause as bug 5730.

There is a bit of an inconsistency on live search.

Search for something less than 3 characters that doesn't exist (eg. xz), and "No search results" is displayed.  Search for something more than 3 characters that doesn't exist, and nothing is displayed.

When there are search results and characters are removed from the search, the search results are not cleared when less than 3 characters remain.

LiveSearch does not operate on anything less than 3 characters.   You get no search on only two, and no results change when deleting from 3.  Livesearch shows nothing if there is no match.

Manual search shows "no results", as a result of clicking "search" or pressing enter while typing characters.  

It may be possible to remove the results when reducing to less than 3 chars, and perhaps have "no results" feedback, but those are enhancements for another report.

As the original issue is non-reproducable, I'm marking as worksforme.  If you happen to find a case of it again, please reopen. The second issue is covered well enough by bug 5730.