I have the same issue. Had people over last night and we thought the guy was crazy when he told us the pool was shocking him. Then I told my wife about it and she thought she was crazy when she felt it earlier in the year.
Went and got a multimeter today to start investigating and then it the web to find out information and here we are.
After reading the series of comments. Where do I start...
I have a 1.5-2volt differential from pool water to concrete slab. There is bonding around the permimeter and no mess in the concrete. Pretty much 0V differential when going from ladder to water (which makes since right?). Is it required that we have wire mesh in the concrete?
Tomorrow I will start checking connections for corrosion. (Figures I just finished the landscaping around the pool and the ground rod is buried under egg rock and landscape mat.)