The Legends title is an attempt at a serious IC belt - something to be defended on Impact while the TNA title is saved for PPV's
I've said it before but i think the Legends belt is an "Appeasing" Title for the "Big Names" so that they have a title to throw over their shoulders. When a young and promising guy gets a decent (3 month minimum) reign, then maybe it can be compared to the IC Title. As it stands with guys like Booker T, Nash, AJ & Foley its basically a 2nd tier world title for the "Big Names" to pass around amongst themselves.