I've always been very big into pc gaming since 1995. I started it with my dad. I hear people bring cost into the argument a lot. And it does have some basis. I bought my current rig over four years ago now. I spent about 650ish or so when I bought it. I only recently upgraded the video card. I did that cause I don't plan on upgrading anything else on the rig till at least the end of next year. Maybe then or a bit after I might do a new pc.
So for less than a thousand dollars. I would say about 850 total counting my current video card. I have been playing basically every game released at 1080 Resolution and high settings. Considering everything else I use my pc for. To me it was never a bad investment. But that is for me. I play mmo's and have a good deal of close friends and family who play games on pc.
The funny thing is. I actually now play my console games through my pc. Just so I can continue to have voice chat if I want. I just clone the hdmi signal going to my tv, and send it to my monitor . Then at the desk I use my monitor to split out the audio and run that in my pc's line in. Then I have all my audio coming through my main headphones. So I can skype, voip, listen to podcasts, whatever while still listening to the game and playing it.
If you have friends on the pc, and you like setting stuff up personally. It can be a world of fun. If you are wanting to put the investment into it. Plus steam sales are crazy! *Waves arms in the air like crazy arm blowup tube guy*
The main thing though is to keep in mind the costs, the effort (Sometimes you gotta do work around or custom set ups to make something work the way you want. ), and of course the games and community.
The main thing to do is take some time and research it. Find out if you have friends who play on the pc. Find how just how elaborate you want to go with hardware.
Figure out what kinda games you want to run. Are you wanting to run next gen games on your pc? Might want to wait a bit before going into a new pc then. Wait till we know what is in next gen hardware. That's part of the reason I am holding off on doing my next upgrade. The next computer I do at the end of next year or a bit beyond. Will most likely easily match whatever the next consoles are and beyond.
I should say a year or two ago I did get a ps3. As a little treat for myself. I usually end up owning all the consoles every gen. Though next gen I might skip xbox. Just don't care for the way certain things with them and me have went.
Over all though my primary gaming has been a pc/nintendo/handhelds about since 95. I've been pretty content with it. Though it fits my wants. Just whatever you do, make sure to take the time and research it. Especially if your cheap like me. ^_^ Also good luck on whatever route you go.