My biggest pet peeve as a user is when I'm left with no choice but to back out of a site to go download a plug-in. I know I don't. Since we have virtually zero standards for site development, make sure to create a site that degrades nicely if someone doesn't have the proper technology. I can still see the site. An entertainment space should provide ending points or exitways out of particular portions of the site.
Some sites run campaigns that last for days, weeks, or months.
In these cases the site needs to ease its viewers' transition in and out of the experience while keeping them informed that the story is to be continued. Even if your site is running a one-day campaign, the ability to state where a person is in the site's hierarchy is always helpful, and viewers will thank you for it in return visits and referrals. We've all experienced a site that neglects this notion. These are the general guidelines that form a basis for measuring what is expected, and some trouble points to look out for when designing for entertainment. As you may have noticed, most of these goals and expectations are tied into the interface and feedback mechanisms of your site.