This could be such a fine service with just a little attention from the authors. Unfortunately, they don't see the worth.

VT searches the disk (not just the Applications folder -- that's important) to locate and identify installed software by name and version. Then it searches an on-line database for current versions. It reports installed software that has been updated and offers to download and install new versions.

Nice idea, but there are three show stoppers:

1. If the software is somewhere else than in Applications, the install goes to Applications most times. So if, for example, you create a subdirectory in Applications to hold a program and related documentation and program files, the update will be to Applications and not to your subdirectory. Then, the next time VT is run, it still finds the out-of-date version and offers to update the current version it installed in the wrong place.

2. The application identification logic is flawed. For example, with Parallels Desktop installed, VT finds the Parallels uninstaller, Uninstall.app. Good. Then it recommends updating it with the general shareware program Uninstall.app. Bad, even potentially disastrous.

3. In addition, sometimes it identifies software as being something completely different than it is. For example, I have the useful program SyncTwoFolders.app installed. VT identifies this as a game program, SMasterMind, and offers to "update" the folder sync application to the game.

In summary, this is a potentially useful program that you cannot trust, but must check carefully every result reported before relying on it.