I have defined my default browse categories in my user settings profile, but when I go to PictureBrowser all the categories are automatically selected. However the categories you define DO take affect when you click Search and browse torrents the "old" way (i.e. a list of torrent titles). Also if you define your categories for the PictureBrowser view, these settings are not remembered after closing your browser (confirmed in Firefox and Chrome).
Is this a known problem? Shall I report it somewhere?