I have noticed that Google Analytics has started an effort to be more intuitive in detecting search queries, specifically, finding searches that are done in embedded search (ie someone has used the API code to embed Google, Yahoo, MSN or a third party search into their site) and these searches can show up in the keywords. For example, I have two similar sites, one of which is just a place to test new designs and layouts. Both sites have on-site search, with the search results page on the experimental site pointing the user to the appropriate page on my main site. Analytics records traffic from searches from this non-branded internal search page, and shows the keywords in the keyword assesment area, in most cases with the + delimiter included. This may be what is happening in your case. I have also noticed that keywords entered in the internal search function on the main site itself are sometimes recorded in the keywords listing.

It should be possible to view traffic by search engine, and then check the keyword list for each of the search engines and see if one of the lists has all the results with the delimiter - at least it may give you an idea of the source of the problem.

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