Linux has no benefits except that 'maybe' it's a little bit faster .... though stacked up one right to the other, you can compile something just as fast in windows as you can in linux. But to me linux "feels" faster in many ways.
Also, you have ''security through obscurity". Since most viruses and crap are made for windows, you'll at least be partially protected in linux. Not really, but every little bit helps right?
As for is Linux a "tool"? Well, it's like a pick-axe or a hammer. It's how you use it. If you're a command line freak, then linux is where you should be.
It doesn't really have any benefits though. Since ALL your BH work should be done in Virtual Machines anyway.
SEO and BH methods have absolutely nothing to do with linux. For most software you'll need Windows anyway, so you'll have it one way or another.
If you want to get your hands dirty a bit and learn about computers, then Linux is where you want to be. Other than personal gain, it posses no BH method gain.
You can do several things:
* Dual boot. Linux on one HD and Windows on the other
* Single boot with Linux, and keep all VM's there.
* a mix of the above.
For me: Windows, Linux or Mac ... hell even BSD are all the same. I prefer Linux as I'm a command line junkie. Though, as this moment I have 4 Windows 7 x64 virtual machines running on this computer, along with an apache server for code testing and design. I have a on-site *nix server for main storage and some archiving, *nix host for main websites (gotta love SSH access which Windows servers don't really like, and a Win virtual host floating around for ... hmm, 'things'.
*shrug*
Linux is just an environment.
It's like asking, which is better for getting to my 9-5 POS job in? A Hummer 1 or a Skyline GTR? Both will get you there ... it's just the style you choose to arrive in.
-- Kat