Marketwatcher is a library for Windows Phone 7 which can be used to fetch application reviews from the Windows Phone Marketplace. It is licensed with MIT, so you can use the library anyway you want.
The repository contains a sample app which can used to check out how the library is used.
Marketwatcher uses the Reactive Extensions. It may be that the RX is dropped at some point in favor of a implementation which doesn’t require any other DLLs. The library also references System.ServiceModel.Syndication which is used to parse the review data. The referenced dlls are included in the repository.
The Nuget package is coming!