Jack,
This is a Massachusetts thing. Our state constitution allows citizens to gather a petition drive to amend the constitution. If they get a certain number of signatures, the legislature must vote at least 50/200 in favor in two consecutive annual sessions (the constitutional convention), at which point the issue moves to the ballot. The state constitution requires that the legislature vote on the petitions and recently the liberal MA supreme court (the same one that gave us "gay marriage") ruled unanimously that the plain language of the constitution means what it says. The advocates of gay marriage were attempting to get around this by recessing the convention (which requires only 101 votes, rather than the 151 needed to knock out the amendment fair and square) in the name of "equality" and "rights." However, they failed this time and therefore the amendment to ban so-called gay marriage in Massachusetts will continue to the next step (a second vote in the legislature next year).
www.voteonmarriage.org is the site of the group behind this initiative petition.
Thanks so much. I feel informed now!