Bigelow habitat to ISS? So says Boeing

[Dr Mordrid]

This is likely, but not certain, to be the BEAM - Bigelow Expandable Activity Module, a hab used for logistics and as a testbed before their tech is used for other much more interesting projects. That said, a Sundancer can't be ruled out as it wouldn't need another spacecraft (the Soyuz lifeboat or a crew exchange vehicle) acting as a tug to put it in place for berthing.

From an interview mostly about the Boeing CST-100 with John Mulholland, vice president and program manager for Boeing Commercial Programs -

"[Robert Bigelow] has been a great partner and provided us a lot of value," Mulholland said. "They are about to sign a contract with the International Space Station to put an inflatable module up there. Getting that NASA seal of approval will really help stimulate the market."

Sounds like the "balloon" is literally getting ready to go up.