From the kickstarter webpage FAQ linked here http://www.kickstarter.com/projects/...circuit-boards

What is the minimum size (of trace / gap) that the printer can print?

The printer has a resolution of 600 DPI and we've tested making tracks/pads down to SOIC components (pin spacing of 1.27mm) very reliably. We are still pushing the limits to get even finer resolution and be able to use teeny tiny components.

What chemicals does the printer use and are they dangerous/hazardous?

The printer uses Silver Nitrate and Ascorbic acid. Silver Nitrate has been used in applications such as photography for centuries, and while we wouldn’t recommend serving the ink up with dinner, the finished circuits are safe to handle. Ascorbic acid is nothing more than vitamin C.

Looks like a promising first step has been taken. The 1.27mm barrier seems big at this moment. Chips are getting tinier by the day and pitches of <0.5mm are becoming the norm.