51% Mitigation Plan
I want to start by thanking all users, new and old, for making BTC Guild become what it is today. I never expected a service that originally started on a mining PC in my dining room in April 2011 to go this far.

However, recently BTC Guild has started to become "too big". Users of Bitcoin are becoming scared that BTC Guild, either directly or through hacking/coercion, could be used to attack the network as it gets closer to 51% of the network. If this were to happen, it is likely many people would lose confidence in Bitcoin, as a single entity could control the network if it wanted to do so.

I have put forward a proposal of my plans on how to mitigate this threat, but unfortunately nothing can be done without users taking some initiative as well. The following are the actions that will be taken if certain thresholds are crossed:

More than 40% of the Network [last 2016 blocks]
PPS fee will be raised from 5% to 7% on all new accounts. Old accounts will also be increased (PPS ONLY) to 7% after a difficulty change. If the pool eventually drops back under 40% for more than 72 hours, these fees will be turned back down to 5% after the next difficulty change.

More than 45% of the Network [last 2016 blocks]
Getwork based pools will be completely removed within 24 hours. All users on getwork have been warned in the past that it is a unsupported and not advised method of connecting. This should remove ~15% of BTC Guild's hash rate immediately.

More than 40% of the Network again [last 2016 blocks]
PPLNS fee will be raised from 3% to 4% after a 72 hour warning. This fee will be reduced back to 3% once the pool drops back under 40% for more than 72 hours.

If you have questions or comments, please leave them on the forum thread related to this issue: https://bitcointalk.org/index.php?topic=168108.0
April 7th, 2013