I've updated my SMW on Tech Presentations from RC1 to SVN HEAD and it seems that Semantic Links with empty text (actually not empty, but space to work around pipe trick and make them invisible) are not parsed anymore - on http://www.techpresentations.org/Category:Conference_Series
[[Has default form::Form:Conference Series| ]]
Is now displayed on the page as [[Form:Conference Series|]] and it's not supposed to display at all.
The relation does show up in Factbox, but Semantic Forms fails to recognize them (it derives form assignments from such relations on Category pages).
I ran SMW_refreshData.php with -c -p -t and then without any. Twice.
Any idea what might be happening?