Quote from AAAintheBeltway:
(1) I believe selectnet was replaced by supermontage. They would definitely move away from their bid/ask if the market was moving.
I don't trade any Nasdaq so I can't be sure, but after taking the S55 last week this is my understanding: SuperSOES and Small Cap SOES was replaced by SuperMontage. SNET is still functional. And to answer one of the original post questions, I believe that if you SNET preference an MM for under his posted size that is a liability order and he is required to fill you.
Here's some info from Dearborn on the recent changes:
http://www.dearborn.com/dfp/include/Series55TestAlert.pdf