For the Bookmarks widget for Plasma you can now select which folder to use as base menu:
So you can set up a few Bookmarks widgets for your most needed groups of bookmarks. In a row on a panel, or for your different activities, or whatever you want to do.
Also will the tooltip of the Bookmarks widget be set to the name, the icon and the description of the folder. And even better, this data will be automatically updated if you change any of these in the global bookmark editor, like fixing a typo. Even in the settings dialog above the folder data will be updated. Thanks to the nice KBookmark* classes in kdelibs this all was quickly added.
For compile instructions see the link at the begin. Compiles also against KDE DP 4.3.
BTW: If you live in or around Dresden in Germany and want to have some fun and gather some experience running the Linux-Info-Tag Dresden autumn of next year, now is your time to get up and in contact!