You know those "Designed for Windows XP/Vista/Mac" tags that are often seen on hardware packages? They provide the advantage of peace of mind; one can go into the store, purchase a piece of hardware, and know it will work with their system without having to do a ton of research on-line first. No Linux flavor offers that yet, but Ubuntu, being the most popular distro out there right now, might be able to change that.
What I'm proposing is that Canonical set up a hardware certification service, whereby hardware vendors would submit their items for testing (for a nominal fee), and, as long as the item meets Canonical's standards for compatibility with Ubuntu, they get an "Ubuntu Certified" logo that they can display on their packaging and advertising. As for the standards in question, those would be for Canonical to determine, but I'm thinking that it either has to a) be able to download all requirements from Canonical's repositories, or b) come with a simple installer that can install any drivers or software necessary (think .deb files, or scripts to add repositories; not a big wad of source code to compile).
I understand Canonical already does this for full systems, to some degree (
http://www.ubuntu.com/partners/hardwareprogramme), but I would love to see it extended to individual components as well. Wi-fi cards and printers, in particular, could use a program like this; knowing how many of each have severe issues under Linux, being able to quickly spot a compatible one while shopping would be a godsend. Plus, having the certification logo featured in the advertising of prominent hardware vendors can only help raise awareness of Ubuntu.