This happens as long as PE is existing. So it's nothing new. Some even claim that you have more chance to find a claim in a mob spawn. However to my knowledge this is never proved. Regards, Ion
Many people noticed the difference in mining resources distribution here, so that's not actually my opinion
Mining is the same on all the various planets. Just the resources are different on each planet. If ever get in a situation where the claim is hard to get at, you can right click on the deed and there is an option to move the claim to where you are. I think you can move it 75 feet or meters not sure which. But this gets it away from a spawn, or off the side of a hill. I have used it several times and it works great.