For a contrary opinion: Whenever I come across a site anything like whycantichange, I immediately ditch it and glaze over. Those come across as sleazy cheap grabs for money, even if they aren't actually asking for money.
I'm certainly not suggesting that the LW front page should be replaced by a landing page. That particular design does have some negative associations for me as well.
My point is that if your goal is to make the visitor stick around for a while and maybe even participate, then you need to have a front page that encourages him/her to do so. The design suggested by the OP, in my opinion, probably does not.
What if the front page looked a little more like this?
(Please assume that I'm trying to help. If you're polite and constructive (even if you hate this design) Omega will send you bundles of love in the post. If you're rude, I'll personally fund ninja assassins to hunt you down.)