I've been following a trend I've noticed some time ago when google started the "authoritative" site recognition in the SERP's. It first came to my attention when V7N
SEO forum (I'm a member) would rank higher for my targeted keywords? The V7N pages that ranked higher were my signatures in the forums. So, my site that exclusively dedicated to casino content was outranked by a non-casino site based soley on the fact that it was an "authoritative" site.
Here's another example recently reported on the seobook.com site. It's the most extreme case that clearly points to the significance what this really means.
http://www.seobook.com/archives/002374.shtml#more
The article talks about Matt Cutts famous Google bog that merely had anchor text "buy cheap viagra", that quickly ranked in the top five spots in google. his site is not about "viagra", "buying", or "cheap".
What does this mean for our casino portals? It simply means that right now it's not "what" is on your site but "where". It could be more feasible to create a non-casino related site. Gain authority in this site and then market casino content for high placement on the search engines. Also, consider that links for non-casino related sites are not only easier to get, but cheaper as well. From an economical point of view there could be something to it.
I'm only considering search engine placement and not player retention. Personally, I think long term dedicated content and natural links are best, but if you see an authoritative site for sale cheap, buy it!
God help us all if there was a flood of high authoritative sites that wanted our peice of google SERPS for the top competative casino related keywords.