Oklahoma looks like it's about to be the next state to remind the federal government about the 10th Amendment. It sounds great, and I'm sure it's very cathartic.
Beyond that it's really quite meaningless.
I think the states should pay attention to Prof. Randy Barnett's recommendation to "petition Congress for a convention to propose amendments to the Constitution."
His point is that such conventions, once convened, can do just about anything, so Congress would naturally want to avoid such an event. Thus they might be inclined to behave and maybe even offer the states a constitutional amendment to address their concerns. It's certainly worth a try.
Or maybe we should just repeal the 17th Amendment. Instant return to federalism.