Ah. So you're going with the Eclipse rollout strategy of 'only allow old users to use the old UI until we decide everybody should suffer', eh? I guess it will work to silence critique – those who can complain get the old layout they can actually use without gouging out their eyes, so they don't complain, while new users who aren't logged in will take one look at your ugly, bloated, ill-fitting new UI, see that it is ugly, bloated and ill-fitting, and leave forever without bothering to post a complaint on the forums. It's a smart move… until you decide that everyone should enjoy this modern UI, flip the switch, and then everyone is back at your throat again.
Just admit defeat, go back to the drawing board, and come back with a UI that allows you to jam in the ads you want without trying to turn a database into a news site. Like I said earlier, this isn't the Washington Post or the Montreal Gazette. This is a compilation of user-generated information, nominally intended to get you information on things you don't understand and give you further reading if you still need help. If you want to redesign your UI, look to Wikipedia for your answers – especially since it, too, has seen little need to change, given that the optimal way to serve text and images was stumbled upon early in the site's life. Update the header, modernize the text, maybe get rid of the skeuomorphism if you feel like that's a dire emergency, and fix your damn ad setup so it's not entirely broken no matter what UI you use. As shown with the previews of the image gallery update, we're not entirely unwilling to change – just so long as the core functionality and format of the website is preserved in the change, and you resist the urge to mutilate this site into something it isn't and will never be.
If you want to look 'fresh' and 'modern', adapt the current format with new fonts and slightly slicker page elements. If you want to make more money off of ads, make ads that load correctly, quickly and consistently, so that site usability isn't dependent on how strong your adblock is. If you want to make a news site, make Cheezburger the news page and have us go there to get news. If you want more money off of this dying site, ask your userbase nicely and wait for them to provide. If you want to piss off the userbase and kill the site entirely, get your stuff and leave.