In Mac OS X, you can check for updates to Apple software using the built-in Software Update program. OR you can go on the command line and do it with "softwareupdate -l"
There are many GUI based programs for checking third-party versions against [url removed, login to view] or [url removed, login to view], but none of them can be called from the command line, nor have their output on STDOUT or to a text file.
We would like a program that does exactly that: scans for apps in a few designated folders, checks their versions against the mentioned websites, and lists those that need updating and provides URLs for download (as provided by the websites).
You could start from scratch or you can base work off an open source Dashboard widget that does essentially the same work.
The developer of the AppUpdate widget released his code under the GPL. I contacted him and he said this project could probably be done easily. He was too busy to do it himself, but offered to answer questions that we may have during development. [url removed, login to view]
We are open to any estimates for this project. Dependencies for your code not included with a base Mac can be installed. Needs to run on [url removed, login to view] through 10.6.3.