The old one, for now. For one, Eupedia-logo-2.gif in the new one doesn't have the same gradient as the rest of the background, so you can see its box and that looks awkward. It should have a transparent background instead, or a very carefully made matching background.
Also, a good principle of design is that a design theme should be repeated somehow to tie the design together. But there isn't any black or gray blocks or gradients outside of the header, other than at the copyright, which is too far down to have visual consistency. I'm not sure how you could make that better... maybe by having the header color not stretch the whole length of the screen, and by having things like the text ads and travel guide tables in the same style?