There is a definite difference. You can also read my response titled 'progress' for more information. What I had done didn't involve any lasers. It actually ended up just being light therapy. There is significantly less peeling, redness and downtime with light therapy then there is with lasers then there is with chemical peels. Chemical peels can help with surface lines scars, etc but will not heal acne. The Photodynamic light therapy using levulan (L-PDT) will actually heal Acne by killing bacteria and reducing pore size and the overproductivity of sebaceous glands. Much like Accutane except it is external so no harsh side effects.
The other difference with peels is who they are done by. I have had chemical peels which did nothing but they were performed by an esthetician who is not licensed to perform peels to the same degree as say a plastic surgeon. (think 10% solution compared to 40%)with the higher percentage, there are better results but more pain and longer recovery times.
If you still have active Acne (depending on how severe) and scarring as well, with light skin, they will probably suggest the L-PDT with a photofacial(which is a laser light). Like I said in my post below, I think this is the beginning of a revolution in getting rid of acne.
Hopefully that answers your questions. Let me know what you think once you've had a chance to look into it!