I encountered a problem when crawled search results for list items gave URLs based on their display form but not on the Default one – what is unexpected.
So, I decided to investigate the logics how the search engine defines which of display forms to use for search results.
I found the similar problem described here:
After playing for a while with renaming and created date for the forms available in the list, I came up with the following conclusion:
Search engine takes the OLDERS display form (aspx) for list items to construct search result URLs.
[The note is humbly provided by http://www.facebook.com/yury.shpakov]