SEO people inside please -- hosting quesiton

Yes and no.

google has publicly stated in the past that having your own dedicated IP does not add to the value / seo positioning of your domain. What really matters is good relevant content and relevant inbound links from other sites with good relevant content.

different C Classes probably help, but no one has an exact answer.

IMHO it probably helps if you have 2 different domains on their own different C Class, registered at different registrars with different admin/contact/technical info (i.e. different privacy services enabled to stay in compliance)

where is xxxjay? isnt he the SEO master?

Correct. Get as many different hosts / IP's as you can if you plan on interlinking them, otherwise you're doing yourself no favors whatsoever.

Google has also said they have a host-crowding penalty.

It totally depends on what you are planning, whitehat, blackhat, bluehat or whatever silly categories SEO is put in.

The advantages:

- Links FROM your site(s) on all different IPs are a more effective
- Having a unique IP means you can't suffer from any IP penalty other sites may pose on a site (maybe without you even knowing about it). This part is totally overrated, IP penalties are extremely rare.
- Network detection is much harder for bots, although you'd want different nameservers and if you are really paranoid different whois info as well.

The disadvantages:

- Google is more sensitive when finding blackhat stuff on a site with no other domains on it's IP. Your IP won't be penalized, but the site will get kicked faster. Believe it or not, it's a fact.
- It's not foolproof or 100% safe, heavy interlinking will still reveal your network
- Links from many different IPs do not substitute for domain authority and trust, which are much more important, so the advantage is slight.

So, it boils down to a small advantage when building huge networks, but we are talking about dozens if not hundreds of domains to maximize the effect. For 5 or 10 sites, it's pretty useless, since you'll get alot of links from outside your network(s) anyway.

I'd say aggressive techniques, but not overly aggressive -- but I'm planning waves of sites on domains in waves of 10-20 or so domains... so if I inter-link them at all I will need a strategy so they are not penalized.

Hope this is not repetitive from above, I scanned the thread:

Google has stated and it has been implied that 'serious' sites are more likely to have certain technical things in common. Among them, a dedicated server (or servers), unique IPs, long-term domain registration, etc.

Of course this goes into a huge mix of things they look at, but it is pretty much beyond dispute that if you get "checkmarks" in these areas as well as unique content, non-affiliate content/links, solid and related inbound links, etc. etc. you have a better chance at being ranked well .... so, short answer:

Yes, but also try to be seen as a "serious" site in as many other criteria as possible - just having a unique IP won't likely do much.

Should be a given.

If you are linking between your own sites and they are all in the same niches etc, then signup with Baddag and GotWebHost. Do yourself a favor

BINGO to the above quote, Don't listen to the hosts that say otherwise, thats just their way to try to get you to buy their cheap hosting. If it were true than all the big hosts could accomodate anything you wantyed, but it's not true so they don't waste their time on such nonsense...

Doesn't matter, no money in SEO anyway, please delete thread

Actually, the big hosts have told me they don't even want to deal with it. Too much trouble. They would rather sell bandwidth. SEO's don't use much.

That is why they send those requests to me. We have been doing it longer than anyone else. We have it down to a science.