On the following sites you can find a summery of an analysis made of the online poker and gambling industry in the Spanish speaking market.
Conclusions
There is basically one company (Company A) that completely dominates the results in Google (google.es as we have focused our analysis on the Spanish speaking market in Spain) for all main keywords related to poker and they also have very good rankings for other online gambling keywords related to Casino, Bingo, Blackjack or Ruleta (Roulette in Spanish).
For all the main keywords in the poker and gambling industry including “difficult” keywords like Poker, Bingo or Ruleta this company have between 2 to 4 different websites ranked in top 10 and for “less” difficult keywords like Aprender Poker (learn poker) Jugar Poker (play poker), etc. they have up to 6 websites within the top 10 (see Keyword Analysis for more information).
Company A has a portfolio of far more than 700 websites (it is properly way above 1000 but we had to stop our analysis at some point) which they have hosted in groups of 1-50 websites in different servers, with different IP C class, different locations, etc. (the registration details are though in many cases very similar and so is the HTML structure of their websites and the adds and popups included on their websites which have made it possible to detect that the sites are owned by the same company).
There is also a second company (Company B) that seems to be copying this “successful” SEO strategy although they don’t have nearly as many websites and are only focusing on poker.