I don't think the machines Shapeways uses can use that plastic unless the printer manufacturer offers it (without voiding the warranty). I have not seen anything about a recyclable material on the Stratasys website yet.
Statasys' recent deal with Hewlett Packard means this issue is about to be front-and-center. Hopefully they realize that if they they were to ignore recycling options, their whole idea would get shot down by consumers, myself included. Aaron - 40westdesigns.com/blog