Elinton: Ok thanks a lot. I will try that now.
Eli@Echonest.com: Thanks for your answer. However I don't have Rdio ID's in my database. That's what Im trying to do. I was using this guide from the Rdio website http://www.rdio.com/developers/docs/guides/catalog-matching/
It shows how to catalog match my database with echonests, which in turn can grab the Rdio ID's? Is that correct?
It's all a little bit confusing for me, but my impression was that when I have linked all the songs in my db to a taste profile, I can query the Rdio ID's from Rosetta Stone.