Thanks for your replies. I've looked back through ypool to get a rough estimate of blocks per day: 7/15: ~5300, 7/16: ~4900, 7/17: ~3900, 7/18: ~4200, 7/19: ~4600, 7/20: ~4300. The seeming 'slowdown' in personal finds doesn't correlate with an excessive amount of block finds as you'd expect from GPUs being added, or does the difficulty rise faster on primecoin vs bitcoin? Either way, this is a very unique coin and I like helping find new chains. Since I first started out helping find Mersenne primes, it would be very neat if someone could figure out a 'mersennecoin' so more people could earn while helping projects like these.