Forum Moderators: open
Help me out, peoples!
<edit>No spam reporting please. See Forum Charter [webmasterworld.com].</edit>
[edited by: ciml at 8:53 pm (utc) on Mar. 13, 2003]
a) Bought a lot of different domains and put content on them to boost the main site link popularity. Check the ips - if they are all the same then its a good suggestion that this is true. Also check whois to see if they are all owned by the same person, or are on the same nameservers.
b) Maybe the main site is a company who supplies free content to affiliates who have been lazy and just stuck it on their own sites then linked to him (unlikely though). Check for affiliate links, etc
(probably have?ref or something in the referral string)
Even if they are all on different ips with different nameservers and registered to different names, it is still possible that it is just one person with a lot of sites!
I checked its backwards links, and the majority of them are from different domains, but with almost identical content.
Google reserves the right to ban manually for it, and certainly spends a great deal of programming effort to improve their ability to detect and negate it automatically.
Think of it like robbing banks -- it may be good for a quick cash infusion. But in a few weeks you run out of money, and when you return for another withdrawal, the guards are waiting. All in all, not a clever career move if you have any other options.
There are many sites which competing Webmasters would consider spammy; it's up to Google to decide where their priorities lie in helping the searching public have a good experience.
Personally, if anyone I knew wanted a structure involving 500 pages with highly similar content linking together, I'd advise them against it.
netnerd's point about affiliate links is becomming a common problem for search engines, and especially for Webmasters who have affiliates.