Yes, I'm kind of amazed at it myself. I rank fairly well for some of the most relevant keywords now, and that's where almost all the traffic comes from.

What I think I'm doing right:

* Simple to start. As soon as you enter the page you see the table, you just need to press Deal and you've started. No "enter your name", no choosing options before starting, no nag ads.

* Single page sites. The rules for the games are on the landing page, which means it has more content and is likely to be ranked higher by Google.

* Keep it simple. As a programmer I had the urge to create high scores, multiplayer, logins, track results etc, but at the end of the day most people just want to spend 10 minutes playing, and leaving out those things also means it's maintenance free, and frictionless to get started.

Just played Spades for 1/2 hour. Fantastic work! You did the right thing in allowing the player to jump straight into the game upon landing on the homepage. The games itself are so simple that the process of starting a game should be simple, and you've done that here. Job well done!

Thanks!

Funny thing is that I never play them myself after I've finished them. The interesting part for me is creating the computer player, and seeing if I can make him win more than the human players, I have some stats in Google Analytics that can show me that. Since the computer plays like I would play it's kind of like I'm playing against all the players :)

When I'm testing I usually let the computer just play against itself, add ?autoplay to any of the game urls and when you press Deal you'll see four computer players playing against each other...

Why do you have different second-level domains for each game? Why not use one domain with a bunch of subdomains for each game? That way you'd build brand recognition at the same time, and avoid people running out and registering things like "cribbage-cardgame.com"...

Started by accident. First game I made was Idiot, and got the domain idiot-cardgame.com for it, since I had no plans to create more at that time. When I made Crazy Eights I couldn't really use idiot-cardgame.com for it, so I gave that its own domain. After that it was just a kind of pattern I guess. I also had some vague ideas that maybe I'd get more google juice out of having links from different domains to each other.

I have thought about changing it all to one domain, and setting up some 301 redirects, but I'm just afraid to mess up my google rankings. For the solitaire game I re-use a domain, e.g I have http://www.solitaire-cardgame.com for Klondike solitaire (or classic solitaire), and then I have http://www.solitaire-cardgame.com/freecell for Free Cell solitaire.