Subscribe to this feed, replacing USERNAME with your Audioscrobbler/Last.fm username:
Note: in NetNewsWire the redirect goes into an infinite loop, for some reason. Please make sure your aggregator doesn't do this if you try and subscribe.
It fetches your 'most recently played artists' chart from Audioscrobbler's Web Services and converts them into a BlogPulse Search for the top 10 artist names, redirecting to an RSS feed of the results.
Unfortunately, if you have any bands with common words as names (eg Blur, The Police, etc) then it'll probably produce too many irrelevant results. It already leaves out artist names that are just one word, to try and avoid this.