I think this might lead to a more constructive discussion here, considering how this place is much smaller, etc.

Now that the blocksize debate is back in the spotlight again, we all need to be reminded:

A hardfork is difficult to do under any circumstances.

That said, I don't believe that we'll need "100%" as some... ahem respectable folks in the community claim; Bitcoin is nothing without its economy and ecosystem, and what's essential to a fork is that it has the overwhelming majority of economic activity. Assuming the miners are not malicious, they will follow - and they will be onboard sooner and make the process less destructive if they see the overwhelming majority sooner.

Therefore, I propose we compile a checklist of major parties that we need to convince, in order to gain momentum on this. This list will become very useful once /u/gavinandresen, /u/mike_hearn and /u/jgarzik finish their version of 0.11 / 0.11A XT for review.

I'll start with a list. The list is only a starter from my limited knowledge, so feel free to suggest changes:

Exchanges and Payment Processors

• Coinbase
• Bitpay
• Huobi
• Circle
• Bitfinex
• Liberty X
• Bitstamp
• Kraken
• itbit
• Localbitcoins (escrow)
• Paxful (escrow)
• Bitquick.co (escrow)
• 100bit.co.in (escrow)
• Square
• Braintree(?)
• Bitnet (?)
• OkCoin(?)
• BTC-e (?)
• Other local exchanges (?)

Major services/merchants that use a node

Note: Merchants that use payment processors will switch if payment processors are on board.

• Shapeshift
• Purse
• BTCJam
• BLC
• Tradeblock(?)
• Blocktrail(?)
• Darknet markets (?)
• Openbazaar(?)

Major mining pools

Unfortunately Eligius can never be convinced. What a shame. =\

• F2Pool
• BTCChina
• AntPool
• BW
• 21 inc.
• KnC
• BitFury
• Slush
• P2Pool (?)

Wallets

Greenaddress is unlikely to be convinced.

• Electrum
• Armory
• Mycelium
• Schildbach/Breadwallet(?)/anything that depends on bitcoinj will follow the longest chain, so irrelevant
• Coinkite(?)
• Bitgo
• Xapo

Information website

While not essential to the ecosystem, will probably help a lot in getting the words out and hence building momentum.

• Bitcoin.org(?)

Feel free to suggest additions/changes to the checklist. Let's get a roadmap so that we know what to aim for.