Seems that Bitcoinwisdom is using incorrect way of calculating next difficulty, so their predictions immediately after difficulty change are totally off. The reason probably is they take last X blocks speed generation to estimate next difficulty but they are not recalculating blocks generation speed with current difficulty. As the number of generated blocks in current difficulty rises to X, their prediction becomes correct.
You can make an idea about next difficulty change just by looking at bitcoin.sipa.be charts like this one http://bitcoin.sipa.be/speed-lin-2k.png ...Currently it seems for very little difficulty change because current hashrate is fluctuating near the red - current difficulty line.
Topic: drop in mining difficulty (Read 1375 times)
The bitcoin difficulty just went up to 1,418,481,395
One site (bitcoinwisdom.com) says it will go up:
Estimated Next Difficulty: 1,619,198,809 (+14.15%)
Adjust time: After 1909 Blocks, About 13.3 days
But another site predicts it will go down slightly (bitcoinwatch.com)
Next Difficulty in 1909 blocks 1,416,645,623
One site (bitcoinwisdom.com) says it will go up:
Estimated Next Difficulty: 1,619,198,809 (+14.15%)
Adjust time: After 1909 Blocks, About 13.3 days
But another site predicts it will go down slightly (bitcoinwatch.com)
Next Difficulty in 1909 blocks 1,416,645,623
That would be a late xmas present to the rest of us miners 
If someone dropped a nuke on the ghash.io facility it would bring down the global hashrate. Thats probably the only site with enough centralized hash to make a dent for any period of time.
Nope.
Other then a dropping hashrate are there any other factors which influence the drop in mining difficulty of a particular coin?
Cheers!
Cheers!
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