Robert. Just had a quick nose around allmusic and seems pretty funky! Been playing with the music maps. Though they're quite brief, they're interesting.
Not qute the same thing, but a decent review site which may be of use. http://www.metacritic.com/music/ It shows quite a few reviews from various people "in the know". Can help to form a basic impression of what to expect
Robert, that's a pretty good site, not too sure about the 'Artist browser' section though, when I entered Blue Nile as the artist, it gave me The Power Station as a more sober alternative!
As MO knows, I've been trying to find decent review sites, along with http://www.metacritic.com/music/ you may want to try http://www.iq451.com/ it has links to reviews on the net, and customer reviews from Amazon.com and Amazon.co.uk which are often excellent.