It's free to list a component or other item in the Marketplace, though WindowsPhoneGeek will take 20% (30% after beta period) of any sale as a service / commission fee.
The aim of the Marketplace is two fold: firstly to help developers to build better apps, more quickly, by making it easier to find component for Windows Phone; and, secondly, to make it easier for component authors to distribute and monestise their components.
Component and related resources can significantly increase the speed of app development by providing common building blocks of reusable code (e.g. framework, error logger, ratings launcher). For existing component authors the Marketplace is an opportunity to gain additional exposure. WindowsPhoneGeek also hopes to encourage submissions from existing Windows Phone developers who have created components for their own use, but who have not previously shared them due to the additional overhead that this requires.
Boryana Miloshevska, Founder and CEO of WPGeek Ltd, says:
Our purpose is not just to list thousands of low quality components, but to list only those that really can bring value and can help developers to build better apps. So, quality and not just quantity is what we aim to achieve with the WindowsPhoneGeek Marketplace.
The WindowsPhoneGeek Component Marketplace is currently an invitation only beta. However, you can apply for a place on the beta by submitting a request here. The beta process aims to refine the experience for both seller and buyers; it's anticipated a public beta will go live in September.
More information on the Windows Phone Geek Component Marketplace is available here.