Apple has touted WebKit, the underlying browser engine in iOS and OS X as being extremely powerful and versatile for users and developers alike. Building upon the success of WebKit is version 2 which is under active development and will be released with OS X Lion. Will iOS 5 be updated as well?
WebKit2 is being incorporated in to OS X Lion and is responsible for Safari 5.1′s improved speed and stability. The new version of WebKit brings support for split process models which are sandboxed from the Application layer to prevent crashes from bad code.
WebKit2 could come to iOS 5 but will most likely be previewed and incorporated in a future 5.X release.