[dmatthewson]

They cite cost as the issue, that only 2600 users represent half of all comments on their entire system.

I don't know how much they are paying for a third party to manage their comment system, but I will bid $500/month to handle those 2600 users comprising half of all comments, or $1000/month for all comments. All inclusive bid. I can get this tiny number of users running on a pretty modest system.

My proposed system will also save money on subpoenas and moderation overhead by not storing ip addresses and not having paid moderation.

[qu4z-2]

Have you factored in that you need to serve the comments to every user, not just ones that comment? I mean, to be fair, you could probably serve staticish chunks of HTML and update-on-new-comment, but it's a consideration.