1000W enough for 3 GTX470s?

It should be enough, but I don't know for sure. I would get that it would be fine so long as you don't also overclock the 470s and run Furmark   . You could try it out and let us know though  .

It really depends on the quality of the PSU. I'm not familiar with OCZ's power supplies, but a TOL Antec or Corsair rated at (or around) 1,000 watts can actually support much more than that. You have to keep in mind that the advertised wattage takes efficiency into account, and many units can easily power more than the number on the box says, albeit at a lower efficiency percentage. People are very confused about power draw, how much power they need, what makes a good PSU, etc. In your case, I'd recommend you at least look into it - perhaps call the manufacturers and ask them for their opinion.

It is actually the only PSU - Gold certified in the market, so I think it has to be a very good quality

It's not the only gold certified but it WILL handle 3 gtx470s if you dont have a core i7 at 4ghz with like 1.45v and like 10 harddrives

Do you suggest 1200W for TriSLI on 470's because of his CPU or something?

Cause your signature says you have a 1KW PSU with TriSLI 470's, and an X6 CPU   Just curious.

I only have 1 harddrive and my motherboard is a MSI Trinergy with i7-860 at 4.0 GHz, will it hold everything?

Your cpu, o/c , can probably use up to 200+ watts. The 470's rated for 215. If you go for it, just remember that if you o/c your gpu , its by a factor of 3.
http://www.xbitlabs.com/articles/cpu/display/power-cons...

I figured the 1200W PSU had to do with the i7 OC. Apparently Psycho's X6 OC uses significantly less juice.  

Ylready saw that review but it sayas that it pulls 794 including a CPU OC and everything in their system, not the GPUs alone.