I don't live a paleo diet[1], but I think the focus on fresh foods is good. Just like anything, there may be a kernel of extremely important wisdom that gets surrounded by a huge amount of marketing to make money off of it (think agile programming as another example).
I also have yet to meet[2] a scientist whose word I would trust as the last word on the way I should eat. On the other hand, I've met a lot whose words have influenced how I eat. And based on the reading I've done, we are still so far from really understanding how the body processes food that the only sane approach is to read a lot, experiment on yourself, and monitor the results[3]. Unfortunately, there are just far too many people trying to sell something[4] when it comes to food.
1. I've settled pretty close to Atkins. In fact, one of the things I really like about Atkins is the "on-going weight loss" phase where you literally experiment, journal and measure to find out what is working for you.
2. "Meet" in the "I've read" sense. I'm always looking for more to read on this topic. Due to lack to good information being available, I passed 350 pounds. It took surgery to have a chance to start again; then a lot of studying to take advantage of that start.
3. The scale may be the worst way you can measure your progress. Blood tests are good. A journal of the way you feel is also good.
4. It is sad that, even the best intentioned scientists, still need to "sell" their work to their funding agencies. I don't have a concern than anybody is outright faking things; the concern I have is that anything that doesn't match the current dogma as decided by the FDA, USDA, etc, is getting silently thrown away. Not just "not published", but not even submitted for fear of what a result that challenges the orthodoxy can do to one's career.