Since I switched over to linux as my main OS 2.5 years ago I've had a couple of major hardware conflicts that have kept me from running on certain devices or hardware components. Linux is maturing greatly. A wide, ever increasing, range of components are supported.
Luck played a large role in my switching over to linux. I had an asus g60vx gaming laptop at the time. Installing ubuntu 10.04 was absolutely hassle free and all hardware was supported by default. In addition there existed propriety drivers for my nVidia graphics card. The first install is absolutely crucial in retaining or switching a user to linux (something the community would absolutely benefit from). Switching is becoming less of an ordeal. Manufacturers like Lenovo and Dell make it very simple to switch over with full hardware support.
Both Lenovo and Dell have 'Ubuntu Certified' machines. Any speedbump to installing and running a system smoothly can ruin someones chances of converting. Individuals do not want to deal with technical issues, especially on their recreation machines. If Ubuntu didn't offer a list of approved hardware and laptops, I personally would have just gone with OSX and virtualized linux. Not because I like mac (quite the opposite) but because it is POSIX and it just works with the hardware. Having to debug, troubleshoot, fiddle with hardware/software all day at work turns me off to doing it at home. I no longer like spending hours of my small amount of free time debugging linux hardware issues.
There are a couple of reasons I became a Lenovo loyalist:
1. They offer ubuntu certified machines with compatible hardware.
The hardware components they choose to use have open source drivers. When I install fedora or Ubuntu things just work. Unfortunately there are still issues on messages boards of some certified machines performing poorly. I've lucked out and have not hand an issue with the T and E series.
2. Hardware is completely business focused.
Lenovo hardware is absolutely no frills. This can be seen in their designs that have barely changed sine the first thinkpads. Lenovos aren't pretty. They are functional, reliable, have an extremely high build quality and are military spec. Plastic is used all around. But the 'cockpit' is the most comfortable laptop I have ever used. The keyboard is by far the nicest and most comfortable offered on any portable device.
3. Finally, being conscious of Linux users goes a long way to earn repeat business.
Most of the large companies offer some sort of linux compatible machines. Dell has some laptops and HP has many business desktops. Lenovo goes that extra step and has most of its business/professional laptops certified.
Companies like Lenovo and Dell are helping to lower the barrier to entry for new Linux users. When linux is not a hassle it increases a user's chance of regularly using linux.