Just wondering why the radio on the n70 is only a mono radio when the music download side is in stereo?

What makes you think the radio is only mono?

I know it is I work in the hi fi world listen to classic fm thru the fm on the phone and them on a stereo fm tuner notice the difference, or on my local radio station they played a old 60s tune thru headphones on a normal radio had a listen very wide sound on nokia no seperation at all.