Thought Works released their latest version of Selenium(Selenium 2.0).Selenium 2.0 also contains 3 components Selenium IDE,Web Driver and Selenium Grid.
In Selenium2.0 Remote Control is replaced by Web driver.This Web driver is very quick in test execution when compared to Selenium RC.
Major advantages with Web driver when compared to Selenium RC is
1.Selenium RC uses a Proxy through Java Script to launch a browser which usually takes some time,but coming to Web driver it supports some native apis for each web browser(Special api for each browser)so that web browser can be launched quickly using these apis.
2.The API of SeleniumRC is quite complex when compared to Web driver api.
Till now Webdriver supports only Java api.Drivers for all other langauges are still in development stage.
The Webdriver api will be available in the following link