I don't really have any training in this area (I didn't study anthropology, history, biology or nutrition in school), but while the implementation of paleo might be flawed the principle makes sense to me - eat what we evolved to eat, exercise like we evolved to exercise. At least that's how I see it. I'm not all to familiar with what it's actually like.

I think that we could probably all go for eating less meat and a lot more fruits and vegetables. The flesh of other animals tastes so good though!

Whenever I've been in shape I haven't stuck to any diet or strict regiment. It's pretty easy to loose weight (in principle, not in practice) if you do some moderate exercise (like take a run a few times a week, take the stairs, etc) and avoid restaurants and processed foods. I think when you start cooking for yourself, you'll end up eating a lot more raw "real" food and will find it hard to cook the really unhealthy stuff you might feel totally fine about ordering. It just kind of works itself out.