Its weird. Many cryptonote currencies seem to have the same effect. A hashrate increase of roughly 10x in the last few days.
I doubt suddenly everyone started mining them. Unless there have been developments like a new gpu miner that I don't know of. In which case, cpu mining (the main thing keepeng them attractive to miners) is gone
What other cryptonote cryptos are currently experiencing an unhealthy growth of difficulty and hashrate? Is boolberry among them? Well someone must be secretly trying a proprietarily made miner. Expecting little to no impact on clown coins with no liquidity... but monero... That one may see a dumpage as a result of 10x higher selling pressure from miners.
Bipcoin for sure has had problems for days. Blocks take hours.
Nic Nac occasionally has similar slowdowns but not all the time. Its normally a very low diff coin (like 4-10Kh) and now consistently over 30Kh. But the chain is slower now so I doubt the hashpower is really there