The question is a lot like "What car should I buy?". There are a lot of people who will say what they like and don't about any product. So yes, it does come down to what you are comfortable with. You can buy different models and there are different price points for each model too.

Here are a couple things to think about, when selecting an operating system.

1. What are you planning to edit ? If you are primarily doing video for the internet, then most low to mid range computer systems should work. You can also use software that is less expensive, like Final Cut Express or Sony Vegas 9. If you are planning to do a lot of animations or AfterEffects work, then you will need a computer with more RAM and a faster processor and video card. You can of course get high performance systems in either operating system, but the task you are doing, might have specific software that may lead you to one or the other.

2. I would look for a friend or acquaintance who is doing what you are doing, or want to do. There is a lot to be said for having someone with a similar system to help you out with any questions that you might have. But I also know that I have been caught with this. A client of mine that I work with now went on the recommendation of a video editor, to go with PC. That is what he was most familiar with. It turned out that he didn't do any of the editing and I probably would have gone with Mac, if I was there at the time.

3. Consider if you are doing work that you will have to send somewhere. If you are always sending a video out to be color corrected, then find out what they are using so you can transfer it to their system easily, for example.

For either Mac or PC, you can find most of the options that you will need. So, yes it does primarily come down to your background, experiences, support system of friends, and what you are comfortable with.

Kdenlive for linux is pretty cool because they have a liveCD which you can boot off of to try out if you are on an PC or intel based Mac.

http://kdenlive.org/user-manual/downloading-and-installing-kdenlive/live-demonstration-dvd-or-usb-storage

I'd wait for livecd version 0.7.6

Well, if you ask someone that uses FCP, there's only one recommendation. I think it's whatever you're comfortable with.

david has a good answer there. if you find a program on your OS that works for you and gets the job done, then use that. i love apple and FCP for editing, for sure. but i know a lot of people who edit on PCs who love Vegas and Adobe Premiere. IMHO and from the demos i've seen at the Open Video Conference, Linux editing is not there yet.

this is kind of a subjective question (should get that tag).

I for one can recommend Apple/Mac OS X because it is shipped with a very simple (alas good) video editing software called iMovie which is very good vor VERY basic things without long learning AND it runs Final Cut, which is one of the best (as in biggest and most expensives) video editing softwares.

Impressingly, Final Cut is easier to learn for young people than Avid or Premiere, the other best/big video editing softwares.