The news came from Virgin Mobile USA's Facebook page, which features a picture of the device (as seen below), and says that "...we're happy to confirm that our next handset launch will be the Samsung Intercept. Check out the photo below, get excited, & stay tuned over the next few weeks for more information!"
The "next few weeks" bit sounds promising, but that was referring to "more information", so we can't venture a guess as to the actual release date. Logic would put the release some time before Black Friday.
Virgin Mobile's current lineup includes the Kyocera Loft, the LG Rumor 2, the LG Rumor Touch, and the BlackBerry Curve 8530.
Samsung Intercept Review
source: Virgin Mobile USA (Facebook) via Engadget