Twitter opened up it’s “firehose”—the full stream of public tweets—to seven new companies today. Previously, the full stream was made available only to Yahoo, Google and Microsoft; other developers only had access to rate-limited offering.

The seven companies privileged with the stream are Ellerdale, Collecta, Kosmix, Scoopler, twazzup, CrowdEye, and Chainn Search. Twitter says “these companies range from funded startups to part-time, one-person operations.” One of them—Chainn Search, doesn’t even appear to have a web presence yet.

Twitter is likely taking the size of the partner—and the potential drain on Twitter’s servers—into account in the pricing. Bloomberg reported that the Google and Microsoft deals added up to around $25 million, enough to make the company profitable in 2009. You can be sure the one-person startup isn’t paying that much. Twitter says that to deal with the variously-sized partners, “we came up with a fair way to license access that scales with their business.”

There’s clearly monetization potential here, and the company has invited any other company that wants a taste of the hose to initiate a conversation. The fact that no deal terms have been disclosed indicates Twitter will likely size up each partner as they come in, and demand a toll proportionate to their size, while fostering the budding ecosystem of bootstrapping developers with a bit of favoritism whenever appropriate.

image credit: http://www.rffd.org