This feedback led us in Vertcoin_dev to discuss and test the Kimoto Gravity Well difficulty algorithm (abbreviated to KGW in this post), as used in Megacoin originally, which has now found it's way also into Anoncoin, Ron-Paul-Coin and others following issues they had with multipools stranding them at high difficulty.
KGW retargets every block, smooths adjustments, and copes extremely well with variations in network hashrate, with block times remaining stable and quickly following changes in hashrate.
Here is a graph of MEC hashrate vs. difficulty, where you can see how smoothly and consistently KGW tracks:
We want to address any issues BEFORE we have a problem like that with VTC, so following private testing on the testnet, we have validated KGW for Vertcoin and intend to release an updated wallet and fork in the next couple of weeks.
We expect to release the new wallet, which will also include updated N-factor scheduling (also in response to community feedback), sometime around Monday the 27th or Tuesday the 28th of January 2014. Please also see the N-factor scheduling poll at https://bitcointalksearch.org/topic/poll-vtc-vertcoin-n-factor-scheduling-431092
https://forum.megacoin.co.nz/index.php?topic=893.0 gives an excellent overview of KGW.
Following the changes, everyone will need to change to the new wallet. We will contact pool operators to ensure a smooth changeover there, but we also need to allow time for users who may not come here so often to see the requirement for a new wallet and update, although, if they did not update, they could do so later without loss of funds or similar problems, it's just that their old wallet would not recognise new blocks after the changeover.
We want to balance giving people time to see there has been a change, with the desire to fork quickly so as to better protect and strengthen the network.
We'd like some feedback on how long after wallet release we should allow until the block height at which KGW takes effect. Please register your votes above.