Let's not forget the issues surrounding network centralization and what that may do to confidence in Bitcoin itself (the hand that feeds). We should also keep in mind that mining directly to an address you control has the advantage of requiring no third party trust. Many of us have been around long enough to see miners lose revenue because the traditional pool they mined on was hacked (I'm not suggesting this would happen at BTCGuild, only that it is not beyond the realm of possibility). I do hope the miners consider all of these issues when choosing how to deploy their hashing power.