To make visas available, we would amend immigration law to create a new EB-6 category for immigrant entrepreneurs. We would draw from existing visas under the EB-5 category. The EB-5 permits foreign nationals who invest at least $1 million in the U.S., and thereby create 10 jobs, to obtain a green card. In areas where unemployment is high, foreign nationals need only invest $500,000 to obtain residency. Though roughly 10,000 visas are annually allocated for the EB-5 category, less than half were used in FY 2009, so the addition of immigrant entrepreneurs should not present an unreasonable burden.
http://startupvisa.files.wordpress.com/2010/02/dc-startup-vi...
This merely branches a new visa off from EB-5, which is separate from, and has different intentions than, EB-3. EB-5 visas are not all being used up anymore, so both Senators are attempting to put those waisted EB-5's to good use. They imply that the proposed EB-6 visas "should not present an unreasonable burden" on the system.