You’re going to see different opinions and approaches to these questions, but here are my personal answers:
My question is – how do gambling affiliate webmasters measure a site’s ability to convert?
That’s a simple matter of looking at # of conversions divided by the amount of traffic.
What’s a good method to test?
Make sure that if you’re running multiple sites that you can track the results from the different websites. Playtech casinos, for example, allows you to set up multiple profiles to link to, and you can run reports by profile.
And how much of the ‘sell’ is the portal’s responsibility and how much is the poker sites’?
IMO, your job is to drive traffic and do a reasonable (even minimal) job of preselling. Lots of people have different approaches. Some people are comfortable running very “sales-y” sites, while others prefer to provide a lot of content and just give the affiliate programs exposure on their content pages.
Should I stay focused on getting lots of clicks and let the rest take care of itself?
I think so, but there will probably be 2 people here who disagree with me on this point for every 1 person who agrees with me.