It's plenty mature, just unsupported by the vendors of the programs you use.

I'm essentially the same way, I've got 80GB of games installed via Steam that I don't really want to fight with Wine to get working, much less the terrible ATi drivers for Linux. As a result I have VMWare workstation going with multiple Ubuntu sessions, each far more powerful than the hardware I've been able to dedicate to it before.

For me it goes like this (true story):

"How were you able to get this debug driver and test suite for our hardware going so fast?"

"Because it's running Linux"

The transparency provided by the kernel, and control provided by the user space makes it extremely easy to learn how to write a driver. Contrast this with Windows, where tools and information are locked up behind extremely expensive paywalls, or are extremely obscure and hard to locate.

In fact I can't think of anything outside games or Windows-only software where "Because it's running Linux" has been a negative.