Depends what you call powers. Theoretically, the monarch still rules and the government runs things at his or her pleasure. Practically, that means that the Prime Minister keeps the monarch in the loop on what's going on, and might listen to their opinion, but that's about it. One reason the monarchy survives is that they've learned not to interfere.
On the other hand, they do a lot of charitable work and they draw attention to their pet causes by their presence, so there's that.
I thought it was something like that. I thought they actually had no legal say in anything. I knew they did charitable causes. William and Harry both serve/served in the military. I think some FReepers are being quite harsh on them. They obviously have every advantage in life, but they seem to be decent people. (I like Harry the best)
The Queen does not rule, she reigns.