App Update is a free Dashboard Widget that can automatically check for updates to your installed software. It supports Apple’s software directory, MacUpdate and Version Tracker. It will present you with a tidy link list of all the updates found, enabling you to read release-notes and download the the updates quickly and painlessly.
Pros: App Update is a much-needed widget, with a simple and easy-to-use interface, which checks for available updates to your installed applications.
Cons: None significant.