The VIP membership that comes with the LCE gets you -- on a very surface level -- 5 of the hottest cars in the game and recognition within the game and on the website that you're a Forza VIP who has purchased the LCE. You guys already know which 5 cars are included in the VIP package. Recognition in the game and on the site means you'll have a little insignia to tell the world that you bought the LCE.
VIP is also tracked on our servers and I will be working with Fred on creating a bunch of exclusive liveried cars, as well as tuning files, layer groups, and more from the best of the community and gifting them en masse to all VIP members. It'll be like logging in one day and getting cool stuff because you're a VIP. I don't know how often we'd be doing this but it'd be at least once a month and whenever I have cool stuff to share with all our VIP members I'd just drop 'em into your inbox through our servers.
As for that whole cars and tracks rumor, I can't comment on that now but let me just say it won't be limited to VIPs. Everyone will be happy.
Also, the LCE package is very sexy. It's really the DEFINITIVE retail version of the game.