I've been doing quite a bit of AIP (autoimmune paleo) research myself lately because I think I may have an autoimmune disease affecting my GI system.
From what I have gathered AIP removes more foods that are potentially inflammatory and/or have proteins that contribute to leaky gut or immune response not already eliminated by regular paleo. Regular paleo of course eliminates casein (if you're dairy free), gluten and legume proteins that are common allergens and irritants. AIP adds to that list eggs (mostly because the whites have protective proteins similar to those in grains and legumes), nuts, seeds, and nightshades.
I definitely think it's worth looking into. The idea is not to stay on strict AIP forever (hopefully) but to be able to reintroduce some of those foods, once healing has occurred, if they don't cause symptoms. Of course, for many people just strict paleo is enough, and I think you're willingness to do the plan will also affect your success - and if your symptoms aren't that serious it might be hard to get the motivation. An asymptomatic celiac person may feel that just strict gluten free paleo is plenty for them, where someone with MS or Crohn's might be more motivated.
Anyway, if you really want to learn more I'd definitely recommend The Paleo Mom (http://www.thepaleomom.com/), she has several posts about AIP and has a book about AIP, The Paleo Approach, coming out in the fall. Practical Paleo, the book by Diane Sanfilipo, also has a 30 day AIP meal plan and recipes.