The Omni Group has announced the release of OmniFocus 1.0, their task management tool for Mac OS X. It costs $79.95, and is available for download now (this follows a lengthy beta period).
OmniFocus is, at its core, a "personal productivity application" designed to help you capture and organize your thoughts. You can use it to store, manage and process action items; tasks can be assigned to projects and stored within contects. Visual cues can highlight what you're supposed to do next.
OmniFocus supports the "Getting Things Done" work-life management method developed by David Allen, according to The Omni Group. It imports data from kGTD documents, synchronizes with iCal, handles project and task filtering, supports file attachments and saves viewing perspectives.
System requirements call for Mac OS X v10.4.8 or later.