Careful with this.
I haven't downloaded yours to see what it's doing but I assume it's what I do with mine: use the rovi music findr JSON API to select the moods/themes/genres and then query the local MM database for matches after setting up the filter.
AMG (owned by Rovi now) is notorious for coming after people for publishing apps that use their data in this way. The Music Findr API, while easily used, is not public and you could get into hot water quickly.
Were I you I would allow for a customizable user-agent request header and also make sure that referers and cookies are being properly imitated. I would also limit the request speed. But that's me....




