Sketches 0.5 beta has just been released, it should be available soon via Installer.app.
The biggest feature is support for multitouch drawing, making it possible to easily draw shapes such as ovals, rectangles, lines or arrows. Multitouch has been integrated with the "single-touch" mechanism in previous versions: you can use two fingers to create a shape, or just one to continue drawing free style, just like you were used to.
Sketches 0.5 is compatible with iPhone and iPod Touch devices running firmware versions 1.1.1 through 1.1.3, adapting to platform specificities automatically. The bug that caused only one photo to be exported to your photo album has been fixed, and sending sketches via email has been made a bit more user-friendly by providing visual progress indications.
More details about these new features and other improvements are available in these iPhone-ready release notes.
We hope you like this release!