Well, that didn't take very long: our crafty friends over at RootzWiki have already brought the I/O Android 4.1 preview build to both the GSM and Verizon Galaxy Nexus. Forum member B16's original GSM dump, followed by jdkoreclipse's VZW versison, have been tinkered with throughout the night and appear to be working quite well. It's flashable through Recovery after a wipe and a cleared cache, though as always we suggest you backup before playing around. After spending the morning snacking on Jelly Bean I can report that the Verizon build is near perfection, with even LTE working beautifully. As always, bugs are possible, especially since this is merely a preview build. If you've got the guts and the sweettooth, download links can be found at the source.