Web Processing Service 1.0.0
Somehow, I have missed the OGC press anouncement, or will there be none? Whatever, the WPS has been released as an implementation specification at OGC after a long trail. All the documents are available through here. The schemas can be also downloaded from here.
Just in time, 52north released a new version of the 52n WPS, which implements this new version of the WPS interface specification. The 52n WPS is available as open source and implements all the features as described in the specification. You can get more details about it at the 52north wiki.