A bit of a change from me today ... I'm not going to mention Windows. Well, unless you want to get really meta and count the last line ...
I think last.fm support has always been one of the cool features of Amarok, and as has been mentioned here before, with the services framework of Amarok 2 I'm taking the opportunity to revamp it a bit.
So far I don't have anything really graphically impressive to show for it, but under the covers the old code has been completely ripped out, and replaced with a new codebase, which uses code from the official client to do the heavy lifting. Kudos of course to the last.fm guys for making their client available under the GPL!
What this means for users is that since the scrobbling of tracks and playing of the radio are now using the same protocol (and even largely the same implementation of the protocol) as the official client, breakage should be a much less common thing.
I hope to get working on the interface to last.fm in the services panel in the near future, but until then you can just paste last.fm URLs in the "Add Stream" dialog like any other streaming source.