Whitespace doesn't exist just for the sake of being pretty. At least to me I find this mockup much more readable than the current design, as the space between links clearly separates them. This makes it much easier to read their titles.

I agree. My intention is to use white space to separate things, vs lines or other graphical distractions. Having said that, I still need to work on the list part of the design.

There will be less white space and it will be used more scarcely, however I'd rather use a little bit of white space instead of something like a horizontal line. Wouldn't you agree with this? :P