Today eBay joins other firms in the open source space. Developers are asked to create applications (for eBay and PayPal), based on the site's source code or API (application programming interface). The new dedicated web site is called eBay Community Codebase.
Precursors include Skype, that now has numerous additions, and TiVo, whose 'Home Media Developer Challenge' is coming to a close.
For Skype, that only charges for premium services, this could pose a problem, viz. when an external developer proposes a (free) new service that Skype itself might consider introduce at some point as a premium service. No such risks here at eBay, or so it seems.