I have a huge 100 yr old(i think) pecan tree on my property. It's huge. It is kinda self pruning, so a few times a year it provides me with large enough branches to cut into chunks and dry. I love using it, and do find it less strong than hickory.
As a side note, probably the best hamburgers I have ever had came from cooking them over a bed of 100% pecan coals in my firepit. I had burned up a big branch in my firepit, saw the awesome coals, and decided to make good use of them. Man, I'm getting hungry just thinking about it.