A common practice among arcade webmasters is to have a pregame page before the actual game page. This not only improves their revenue, but it allows the user to gain a quick grasp of the game meaning that you can design a lighter game play page.
For instance, on MyArcadeTheme.com we have a pregame page with a 200×200 advertisement spot right above the play button. Users who visit the page will generate 1 impression on all of your advertisements on the page, and they might even click the one right above the play button, as this spot has a higher CTR (click through rate) than most other spots on arcade websites. Then when the user goes into the gameplay page, they generate a second impression and they are served the actual game which you can implement a preloader script such as that from Copacet, or Adsense For Games.
When you have a pregame page you can get away with showing less on the actual game play page, instead of having to show the description, tags, instructions, screenshots, and whatever else you could show you can show a lot less. On MyArcadeTheme.com we have a much cleaner user interface, and we still get the main point across that this is the game play page and you should focus on the game. However, we have also allowed you to comment so you can give your opinion on the game while you are playing or after you have finished it. This will increase user activity, and it looks stunning.
What Does Google Say
Google actually outlines it in their policy the use of a pregame page and uses the example that we have setup for you on MyArcadeTheme. In fact, this method shines even more on mobile where the user just wants the game, and little else that can interfere with their enjoyment of the game.
The main issue that some would argue is the user experience, while the interface is lighter and easier, some users don’t like the extra clicking that comes with a pregame page, however some users don’t like the cluttered interface. So it’s a trade off and it is something that you should study of your user base if you plan on integrating a pregame page.