The fellows at Rosh Pina Project have posted a video and brief comment on some idiocy which seeks to claim Gentile Christians are somehow Israelites via the "lost" tribes. RPP also posts a link to a critique (better, demolition) of this teaching by Derek Leman, a North American blogger and leader of a Messianic synagogue.
But what's really interesting is the manner in which the thread develops on the RPP website, which helps to demonstrate some of the internal issues - particularly surrounding identity - which the Messianic movement is currently grappling with. For some background, one of the comments is from a former MJ who has returned back to Judaism, Derek Leman (a Gentile currently undergoing conversion to MJ) also comments, as do several Jewish believers (watch out for Dan Benzvi). Fascinating stuff!
By all means add your comment at RPP, but please add any here too for if anyone wants to discuss some of these issues. The Gentile church is, by and large, ignorant of some of these issues facing the Messianic movement.