Note: This review addresses the 2009 version of the software.
DriverScanner takes a good deal of the pain out of finding and updating old drivers, which can help improve system stability and performance.
Where you'd normally have to dig around in Windows to find the version of drivers for your video card, sound card or other devices, and then search online for available updates, DriverScanner scans your system to discover current driver versions and tells you which are out-of-date. You can then click a button within the app to download the new driver, and then another to install it.
The utility provides an estimated risk factor for updating a given driver based on the likelihood of system problems, and will not automatically update those it deems risky (such as SCSI drivers). There's also a handy backup and restore feature that you should definitely use before updating any drivers, so that you can restore what you had if there are any problems with the upgrade.
Scans are relatively quick, and you can choose to ignore certain drivers (such as those deemed risky) so that they no longer show up in the out-of-date list. You can view scan results based on out-of-date drivers, all of them, or only those you've ignored.
While useful and easy-to-use, DriverScanner isn't cheap; it'll run you $40 for the first year ($30 after a current $10-off promotion) and $30 per year thereafter to renew. You can use it on a free trial basis to scan for outdated drivers, but can't download or update drivers until you register the app.