Word straight from the source: Matt Mullenweg says that the WordPress team is working on an iPhone-native WordPress client. The software will be available free in the iPhone App Store, and its code will be open source.
iPhone WordPress Client is Coming
July 10th, 2008
[...] WordPress iPhone application that we first referred to just twelve days ago has been officially released. WordPress for iPhone lets you post to both self-hosted WordPress [...]
July 22nd, 2008