[Sam Bauers]

I don’t really see what the difference is between “local” and “remote” gravatars, they are all remote to end users. I would suspect the changes by Automattic to the serving will be somewhat better than you imagine. Gravatar used to run from two servers, Automattic have a fair few more than that I believe, plus better caching setups. I guess we’ll have to wait and see, but it would be a shame to add options like local caching on top of the simplicity of the Gravatar idea.

As for the Ruby on Rails issue. I’m not 100% sure that the actual Gravatar serving uses Rails, it does use Ruby though. Ruby can scale, it’s just a little less used than PHP and I think it takes more resources to do it. There are a few scaled Ruby on Rails apps out there that are much more complex than Gravatar too, I’m thinking of the ones made by 37signals for example.