This was merged into master by Aaron Patterson during his RailsConf keynote (Github commit)
Where caching is applicable.
The caching is performed on the SQL statements generated (.find for a model is usually called with the same scope) so I think people will see some sort of boost.
At it makes sense anyway, why should AR have to re-generate SQL it just just generated micro-seconds ago just because the ID changed from 2 to 3.
I love the idea that Tenderlove merged it into master live on stage. :)
Seriously, I can’t wait to get this in my production code. It seems like a no-brainer to speed up my queries.