Just an FYI in case like me you leave amarok running at times... don't....
Amarok memory leak when changing tracks https://bugs.kde.org/show_bug.cgi?id=298627
Easily reproducible - just load up a playlist and select the repeat playlist option.
The only plugins I am using are mass storage device and lastfm.
I ran the following command to document the leak: top -b -d 150 -p 11866 > amarok.txt
I then imported the results into a google spreadsheet you can view here: http://goo.gl/Q4bZw
Memory utilization started out at 7.4% and ended up at 31.9% after approx 48 hours. The leak is steady and unrelenting. I ran the same playlist under QMMP during the same period and memory utilization was steady at 2.5% throughout the period.