How about some free speed? Well, here you go. Rails 3.0.3 includes a much faster version of Active Record that reclaims the performance lost when we went from Rails 2.3.x to 3.x and then some. Aaron Patterson has done a phenomenal job benchmarking, tweaking, and tuning the ARel engine that underpins Active Record 3 and the result is Teh Snappy.
You can read more about Aaron’s work in his ARel 2.0 write-up. If you dare, you can also have a look at his RubyConf slides that went over the rewrite and speed-up in even greater detail (warning: there are slides of boys kissing!).
In addition to the free speed, we’ve also included a truckload of minor fixes. So everything just works better and faster. What more can you ask for? Oh, that it’s a drop-in replacement for Rails 3.0 — there are no API changes. You got it.
Note: Active Record 3.0.3 is mistakenly reporting its tiny version as 1 instead of 3. This has no impact on anything you do unless you were specifically checking that tiny version. But if it bothers you lots, it’s fixed on the 3-0-stable branch.