The first is a device that allows companies to have multiple contributors to communicate from a single account.
Called quite simply contributor,this means that although the messages would still come from the company profile name, the author’s profile name would also feature in the byline.
Whether this is the way that revenue streams will arise is anybody's guess but I am certain that there will be a few companies that will want to experiment with this new tool.
This from twitter's development team
This feature is one of several in development; some of them will be visible to regular users and some of them will not. Our goal at this time is to get basic feedback from business users and ecosystem partners. The beta will be released to a limited subset of folks for some time so that we can get an idea of how the features work from a system perspective. After we kick the tires a bit, we'll do a full launch to all business users and ecosystem partners. Stay tuned!